Reference Type: Book
Record Number: 161
Author: Adelberger, E. G.
Year: 1987
Title: Searches for forces weaker than gravity
Series Title: Unknown
Abstract: This paper discusses experiments that are searching for field particles associated with a new force that is weaker than gravity.


Reference Type: Journal Article
Record Number: 162
Author: Adelberger, E. G. ; Stubbs, C. W. ; Rogers, W. F. ; Raab, F. J. ; Heckel, B. R. ; Gundlach, J. H. ; Swanson, H. E. ; Watanabe, R.
Year: 1987
Title: Erratum: New constraints on composition-dependent interactions weaker than gravity [Phys. Rev. Lett. 59, 849 (1987)]
Journal: Physical Review Letters
Volume: 59
Pages: 1790
Abstract: not available


Reference Type: Journal Article
Record Number: 264
Author: Adelberger, E.G.; Stubs, C.W.; W.F. Rogers; Raab, F.J.; Heckel, B.R.; J.H. Gundlach; Swanson, H.E.; Watanabe, R.
Year: 1987
Title: New constraints on composition-dependent interactions weaker than gravity
Journal: Physical Review Letters
Volume: 59
Pages: 849
Abstract: Published
data from two recent experiments testing the fifth-force hypothesis are analyzed theoretically, and new results are
reported. It is suggested that both (1) the positive result of Thieberger (1987) using a hollow Cu sphere floating
in water and (2) the negative result of Stubbs et al. (1987) using Cu and Be test bodies in a torsion balance
operated on a hillside could be explained in terms of a single Yukawa interaction with a nonzero value of the
mixing angle theta5. However, the results of a new torsion-balance experiment with Al and Be test bodies appear
to rule out such an interaction, the only possible exception being an interaction coupled to q5 and limited to a
narrow region with theta5 near -63 deg.


Reference Type: Journal Article
Record Number: 265
Author: Adelberger, E.G. ; Stubs, C.W.; Raab, F.J.; Heckel, B.R.; Su, Y.; Swanson, H.E.; Smith, G.; Gundlach, J.H.; Rogers, W.F.
Year: 1990
Title: Testing the equivalence principle in the field of the Earth: Particle physics at masses below 1 mev
Journal: Phys Rev
Volume: D 42
Pages: 3267
Abstract: A sensitive, systematic search for feeble, macroscopic forces arising from the exchange of
hypothetical ultra-low-mass bosons was made by observing the differential acceleration of
two different test body pairs toward two different sources. Our differential
accelerometer—a highly symmetric, continuously rotating torsion
balance—incorporated several innovations that effectively suppressed systematic
errors. All known sources of systematic error were demonstrated to be negligible in
comparison to our fluctuating errors which are roughly 7 times larger than the fundamental
limit set by the fact that we observe an oscillator at room temperature with a given damping
time. Our 1σ limits on the horizontal differential acceleration of Be/Al or Be/Cu test
body pairs in the field of the Earth, Δa⊥=(2.1±2.1)×10-11 cm s-2 and
Δa⊥=(0.8±1.7)×10-11 cm s-2, respectively, set improved bounds on Yukawa
interactions mediated by bosons with masses ranging between mbc2≊3×10-18 and
mbc2≊1×10-6 eV. For example, our constraints on infinite-range vector interactions with
charges of B and of B-L are roughly 10 and 2 times more sensitive than those obtained by Roll,
Krotkov, and Dicke using the field of the Sun. Furthermore we set stringent constraints down to
λ=1 m, while those of solar experiments are weak for λ<1 AU. In terms of the
weak equivalence principle in the field of the Earth, our 1σ result corresponds to
mi/mg(Cu)-mi/mg(Be)=(0.2±1.0)×10-11. Our results also yield stringent constraints on the
nonsymmetric gravitation theory of Moffat and on the anomalous acceleration of antimatter in
proposed ‘‘quantum gravity’’ models, and have implications for
lunar-ranging tests of the strong equivalence principle. Our 1σ limit on the differential
acceleration of Be/Al test body pairs toward a 1.5 Mg Pb laboratory source,
Δa=(-0.15±1.31)×10-10 cm s-2, provides constraints on Yukawa interactions with ranges
down to 10 cm, and on interactions whose charge is B-2L.


Reference Type: Journal Article
Record Number: 266
Author: Adelberger, E. G.; Heckel, B. R.; Smith, G.; Su, Y.; Swanson, H. E.
Year: 1990
Title: Eotvos experiments, lunar ranging and the strong equivalence principle
Journal: Nature
Volume: 347
Issue: Sept. 20, 1990
Pages: 261-263
Abstract: The strong
form of Einstein's equivalence principle can be tested by comparing the accelerations of the earth and the moon toward the sun. Here, laboratory upper limits on 'fifth forces' are reviewed in order to set an upper limit of one part in a trillion on the earth-moon acceleration difference due to nongravitational forces. Existing lunar ranging data then verify the strong equivalence principle to an accuracy of 3 percent, and improved analysis of the lunar data should bring this precision down to the 0.2 percent level.


Reference Type: Journal Article
Record Number: 267
Author: Adelberger, E.G.
Year: 2001
Title: New tests of Einstein's equivalence principle and Newton's inverse-square law
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2397-2405
Abstract: This paper describes recent experimental work by the University of Washington
Eöt-Wash group on two different topics: a test of the strong equivalence principle and a search
for sub-millimeter scale deviations of the Newtonian 1/r2 law. Our strong equivalence
principle test was motivated by the resurgence of interest in `gravitational' scalar fields, which
typically lead to violation of the equivalence principle for gravitational self-energy. Our
sub-millimetre experiment was motivated by predictions of fundamentally new effects from
`large' extra dimensions and from the dilaton and moduli scalar particles of string theory.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Book Section
Record Number: 127
Author: Adunas, G. Z., Rodriguez-Milla, E., Ahluwalia, D. V.
Year: 2001
Title: Probing Quantum Violations of the Equivalence Principle
Book Title: General Relativity and Gravitation
Volume: 33
Pages: 183-194
Abstract: not available


Reference Type: Book Section
Record Number: 128
Author: Alvarez, C. ; Mann, R. B.
Year: 1997
Title: The equivalence principle and g - 2 experiments
Book Title: Physics Letters B
Volume: 409
Pages: 83-87
Abstract: not available


Reference Type: Journal Article
Record Number: 371
Author: Alvarez, Catalina ; Mann, Robert
Year: 1997
Title: Testing the Equivalence Principle in the Quantum Regime
Journal: General Relativity and Gravitation
Volume: 29
Pages: 245-250
Abstract: We consider possible tests of the Einstein Equivalence Principle for physical systems in which quantum-mechanical vacuum energies cannot be neglected. Specific tests include a search for the manifestation of non-metric effects in Lamb-shift transitions of hydrogenic atoms and in anomalous magnetic moments of massive leptons. We discuss how current experiments already set bounds on the violation of the equivalence principle in this sector and how new (high-precision) measurements of these quantities could provide further information to this end.


Reference Type: Journal Article
Record Number: 372
Author: Alvarez, C. ; Mann, R. B.
Year: 1997
Title: Equivalence principle in the nonbaryonic regime
Journal: Physical Review D
Volume: 55
Pages: 1732-1740
Abstract: We consider the empirical validity of the equivalence principle for nonbaryonic matter. Working in the context of the THεμ formalism, we evaluate the constraints experiments place on parameters associated with violation of the equivalence principle (EVP’s) over as wide a sector of the standard model as possible. Specific examples include new parameter constraints which arise from torsion balance experiments, gravitational redshift, variation of the fine structure constant, time-dilation measurements, and matter-antimatter experiments. We find several new bounds on EVP’s in the leptonic and kaon sectors.


Reference Type: Conference Proceedings
Record Number: 218
Author: Amaldi, E. ; Bonifazi, P. ; Bordoni, F. ; Castellano, G. ; Cosmelli, C. ; Ferrari, V. ; Frasca, S. ; Fujimoto, M. K. ; Fuligni, F. ; Giovanardi, U. ; Iafolla, V. ; Modena, I. ; Pallottino, G. V. ; Pavan, B. ; Pizzella, G. ; Rapagnani, R. ; Ricci, F. ; Ugazio, S. ; Vannaroni, G.
Year of Conference: 1982
Title: Progress Report on the Gravitational Wave Experiment in Rome
Conference Name: Marcel Grossmann Meeting: General Relativity
Pages: 1211
Date: January 1, 1982
Abstract: not available


Reference Type: Journal Article
Record Number: 376
Author: Amaldi, E. ; Aguiar, O. ; Bassan, M. ; Bonifazi, P. ; Carelli, P. ; Castellano, M. G. ; Cavallari, G. ; Coccia, E. ; Cosmelli, C. ; Fairbank, W. M. ; Frasca, S. ; Foglietti, V. ; Habel, R. ; Hamilton, W. O. ; Henderson, J. ; Johnson, W. ; Lane, K. R. ; Mann, A. G. ; McAshan, M. S. ; Michelson, P. F. ; Modena, I. ; Pallottino, G. V. ; Pizzela, G. ; Price, J. C. ; Rapagnani, R. ; Ricci, F. ; Solomonson, N. ; Stevenson, T. R. ; Taber, R. C. ; Xu, B. X.
Year: 1989
Title: First gravity wave coincidence experiment between resonant cryogenic detectors - Louisiana-Rome-Stanford
Journal: Astronomy and Astrophysics
Volume: 216
Pages: 325-332
Abstract: The results of a coincidence search for short bursts of gravitational radiation with cryogenic resonant-mass detectors are reported. No significant excess of coincidences at zero time delay were found. The data have been used to set an improved observational upper limit on the flux of impulsive gravitational waves that may be impinging on the earth.


Reference Type: Journal Article
Record Number: 268
Author: Anderson, John D.; Gross, Mark; Nordtvedt, Kenneth L.; Turyshev, Slava G.
Year: 1996
Title: The Solar Test of the Equivalence Principle
Journal: Astrophysical Journal
Volume: 459
Pages: 365
Abstract: not available


Reference Type: Journal Article
Record Number: 269
Author: Anderson, J.D.; Williams, J.G.
Year: 2001
Title: Long-range tests of the equivalence principle
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2447-2456
Abstract: The equivalence principle can be tested using accurate tracking of the Moon,
planets, and interplanetary spacecraft. Tests with solar system bodies probe the dependence of the equivalence principle on self-energy. Analysis of lunar laser ranges yields the difference in the ratio of the gravitational and inertial masses for the Earth and Moon of ({-0.7}±1.5)×10-13.
In conjunction with laboratory tests of the equivalence principle and spacecraft and VLBI tests
of PPN , one derives |-1|0.0005. Planetary tests are feasible, in particular tests using
Mars. Improvements in Doppler accuracies under development may allow tests with
interplanetary spacecraft. (This abstract is symbolically incomplete because the font does not import, please see http://stacks.iop.org/0264-9381/18/2447?key=nasaads.f175a7d640ef1fac74d2beaa6ef420e9 )
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 137
Author: Babcock, R. W.; Chandler, J. F. ; Reasenberg, R. D.
Year: 1985
Title: Prospects for planetary detection
Journal: Bulletin of the American Astronomical Society
Volume: 17
Pages: 705
Abstract: not available


Reference Type: Journal Article
Record Number: 138
Author: Babcock, R. W. ; Chandler, J. F. ; Reasenberg, R. D.
Year: 1990
Title: Searching for planets around nearby stars with POINTS
Journal: Bulletin of the American Astronomical Society
Volume: 22
Pages: 949
Abstract: not available


Reference Type: Journal Article
Record Number: 270
Author: Baessler, S. ; Heckel, B.R.; Adelberger, E.G.; Gundlach, J.H.; Schmidt, U.; Swanson, H.E.
Year: 1999
Title: Improved test of the equivalence principle for gravitational self-energy
Journal: Physical Review Letters
Volume: 83
Pages: 3585
Abstract: The lunar-ranging test of the equivalence principle for gravitational self-energy is ambiguous.
Although the Earth has more gravitational self-energy than the Moon, its sizable Fe/Ni core
also gives it a different composition than the Moon. We removed this ambiguity by comparing,
in effect, the accelerations of “miniature” earths and moons toward the Sun. Our
composition-dependent Earth-Moon acceleration, ΔaCD/as = \(+0.1±2.7±1.7\)×10-13,
and lunar-ranging data provide an unambiguous test at the 1.3×10-3 level.


Reference Type: Journal Article
Record Number: 271
Author: Bantel, M.K.; Newman, R.D.
Year: 2000
Title: A cryogenic torsion pendulum: progress report
Journal: Classical and Quantum Gravity
Volume: 17
Pages: 2313-2318
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 168
Author: Bender, Peter L. ; Faller, J. E. ; Hall, J. L. ; Hils, D. ; Stebbins, R. T. ; Vincent, Mark A.
Year of Conference: 1989
Title: Optical interferometer in space
Conference Name: Relativistic Gravitational Experiments in Space
Pages: 80-88
Date: August 1, 1989
Abstract: The present design concepts for a Laser Gravitational Wave Observatory in Space are described. Laser heterodyne distance measurements are made between test masses located in three spacecraft separated by roughly 10⁶ km. The major technology issues are: the reduction of spurious acceleration noise for the test masses to below 2 x 10^-15 cm/sq sec/Hz(0.5) from 10^-5 to 10^-3 Hz; and the measurement of changes in the difference of the antenna arm lengths to 5 x 10^-11 cm/Hz(0.5) from 10^-3 to 1 Hz with high reliability. The science objectives are: to measure discrete sinusoidal gravitational wave signals from individual sources with periods of 1 second to 1 day; to measure the stochastic background due to unresolved binaries; and to search for gravitational wave pulses with periods longer than 1 sec from possible exotic sources such as gravitational collapse of very massive objects.


Reference Type: Journal Article
Record Number: 219
Author: Blaser, J. P. ; Bye, M. ; Cavallo, G. ; Damour, T. ; Everitt, C. W. F. ; Hedin, A. ; Hellings, R. W. ; Jafry, Y. ; Laurance, R. ; Lee, M.
Year: 1993
Title: STEP: Satellite Test of the Equivalence Principle. Report on the phase A study
Journal: Unknown
Volume: 95
Pages: 26184
Abstract: During Phase A, the STEP Study Team identified three types of experiments that can be accommodated on the STEP satellite within the mission constraints and whose performance is orders of magnitude better than any present or planned future experiment of the same kind on the ground. The scientific objectives of the STEP mission are to: test the Equivalence Principle to one part in 10(exp 17), six orders of magnitude better than has been achieved on the ground; search for a new interaction between quantum-mechanical spin and ordinary matter with a sensitivity of the mass-spin coupling constant g(sub p)g(sub s) = 6 x 10(exp -34) at a range of 1 mm, which represents a seven order-of-magnitude improvement over comparable ground-based measurements; and determine the constant of gravity G with a precision of one part in 10(exp 6) and to test the validity of the inverse square law with the same precision, both two orders of magnitude better than has been achieved on the ground.


Reference Type: Journal Article
Record Number: 272
Author: Blaser, J. P.; Bye, M.; Cavallo, G.
Year: 1993
Title: STEP. Satellite Test of the Equivalence Principle
Journal: ESA SCI
Abstract: not available
Notes: ESA SCI, Paris: European Space Agancy, 1993, Report on the Phase A Study, edited by Blaser, J.P.; Bye, M.; Cavallo, G.

Reference Type: Journal Article
Record Number: 273
Author: Blaser, J.P.
Year: 1996
Title: Test-mas material selection for STEP
Journal: Classical and Quantum Gravity
Volume: 13
Pages: A87-A90
Abstract: This is a report on the work done of a rather informal working group set up
during the Phase A studies to suggest suitable materials for the test masses of the
differential accelerometers for the ESA STEP-M3 mission. The most important work was
done regarding theory by Thibault Damour (IHES, Paris) and for test-mass design by Nick
Lockerbie (Strathclyde University, UK). Valuable ideas contributed by T Quinn, P Fayet, H
J Paik, A Bernard and P Touboul are acknowledged.


Reference Type: Journal Article
Record Number: 274
Author: Blaser, J. P.; Lockerbie, N.; Paik, H. J.; Speake, C.; Vitale, S.
Year: 1996
Title: Eötvös, an inertial instrument for testing the equivalence principle
Journal: Class. Quantum Grav.
Volume: 13
Pages: A203-A206
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Conference Proceedings
Record Number: 275
Author: Blaser, J.P.
Year of Conference: 1997
Title: Equivalence Principle Experiments in Space
Editor: Wilson, A.
Conference Name: Fundamental Physics in Space, Proceedings of the Alpbach Summer School
Conference Location: Alpbach, Tyrol, Austria. 22-31 July, 1997
Publisher: European Space Agency
Volume: SP-420
Pages: 203
Abstract: not available


Reference Type: Journal Article
Record Number: 276
Author: Blaser, J. P.
Year: 2001
Title: Can the equivalence principle be tested with freely orbiting masses?
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2509-2514
Abstract: The orbit of a free-flying test mass having differing inertial and gravitational masses
relative to a reference mass obeying the equivalence principle (EP), depends on the
EP-violation e as well as on the release conditions. For every orbit a release error does exist
which compensates for the EP effect. The secular term in the relative distance of the masses
(due to orbit period changes) is also dependent on a combination of e and release errors in a
non-separable way.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 277
Author: Blaser, J.P.
Year: 2001
Title: Test mass material selection for equivalence principle experiments
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2515-2520
Abstract: The influence of the choice of the test mass materials in equivalence principle
experiments like STEP on the sensitivity for detection of violations or new interactions is
evaluated. Selection criteria, also taking into account the many technical conditions, are
discussed.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 169
Author: Bowman, Steven Randy
Year: 1986
Title: The Design, Construction, and Testing of a High Precision Lunar Laser Ranging Station.
Journal: Ph.D. Thesis
Pages: 75
Abstract: Lunar ranging data collected over the past decade and a half have allowed the production of empirical models for the motion of the Earth-Moon system. These models fit all the data with a root mean square residual spread of, at best, eighteen centimeters. Much has been learned in the fields of relativity, gravitation, selenodynamics, and geodynamics with ranging data at this level, but more accurate data are still desired. The goal of the thesis is to apply technological advances in lasers and detection electronics to the problem of improving the precision and accuracy of the lunar ranging data to the one centimeter level. Also, by demonstrating the feasibility of improved signal rates and precise automated tracking of the lunar targets, it is hoped that more small telescope ranging stations will become involved in lunar ranging. Towards this end, a new lunar ranging system has been completed at the Goddard Precision Tracking 48 -inch Telescope in Greenbelt, Maryland. It incorporates a new short pulse, high average power laser designed specifically for this purpose. Contained herein are the design criteria, descriptions, and measurements of the performance of the various components of this ranging system. Particular attention is given to the laser system and the testing of new single photon detectors. New techniques of optical coupling and timing calibration as well as preliminary ranging results are described.


Reference Type: Journal Article
Record Number: 278
Author: Braginski, V.B. ; Panov, V.I.
Year: 1971
Title: Verification of the equivalence of inertial and gravitational mass
Journal: Zh Eksp Teor Fiz
Volume: 61
Pages: 873
Alternate Journal: Sov Phys JETP 34, 463, 1972
Abstract: not available


Reference Type: Book Section
Record Number: 129
Author: Camacho, A.
Year: 1999
Title: On a Quantum Equivalence Principle
Book Title: Modern Physics Letters A
Volume: 14
Pages: 275
Abstract: Abstract Available from http://www.wspc.com/journals/mpla/14/1404/0216.html


Reference Type: Journal Article
Record Number: 170
Author: Canuto, V. ; Owen, J. R. ; Hsieh, S.-H.
Year: 1980
Title: Possible determination of the deceleration parameter using lunar occultations and laser ranging observations
Journal: Astrophysical Journal
Volume: 241
Pages: 886-888
Abstract: Using recent determinations of the atomic and tidal lunar acceleration, we propose a model to evaluate qo (average). Our conclusion is that the universe is open for values of Ho close to 50 km s ^-1 Mpc^-1.


Reference Type: Conference Proceedings
Record Number: 220
Author: Carleton, N. P.
Year of Conference: 1988
Title: The IOTA Project
Conference Name: NOAO-ESO Conference on High-Resolution Imaging by Interferometry: Ground-Based Interferometry at Visible and Infrared Wavelengths, Garching bei München, Germany, Mar. 15-18, 1988. Edited by F. Merkle, ESO Conference and Workshop Oroceedings No. 29, p.939, 1988
Pages: 939
Date: January 1, 1988
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 279
Author: Carleton, N.P.; Traub, W.A.; Lacasse, M.G.; Nisenson, P.; Pearlman, M.R.; Reasenberg, R.D.; Xu, X.; Coldwell, C.M.; Panasyuk, A.; Papaliolios, C.; Predmore, R.; Schloerb, F.P.; Dyck, H.M.; Gibson, D.M.
Year of Conference: 1994
Title: Current status of the IOTA interferometer
Editor: Breckinridge, J.B.
Conference Name: SPIE Conference # 2200 on Amplitude and Spatial Interferometry II
Conference Location: Kona, HI, USA, 13-18 March 1994
Volume: 2200
Pages: 152
Date: 1994
Abstract: The first two telescopes of the Infrared-Optical Telescope Array (IOTA) project are now in place and yielding
data at the Smithsonian Institution's F. L. Whipple Observatory on Mt. Hopkins, near Tucson, Arizona. The IOTA collectors are 45 cm in diameter, and may be moved to various stations in an L-shaped configuration with a
maximum baseline of 38 m. A third collector will be added as soon as funding permits. Each light-collector
assembly consists of a siderostat feeding a stationary afocal Cassegrain telescope that produces a 10-X reduced
parallel beam, which is in turn directed vertically downward by a piezo-driven active mirror that stabilizes the
ultimate image position. The reduced beams enter an evacuated envelope and proceed to the corner of the array,
where they are turned back along one arm for path compensation. The delay line, in one beam, consists of two
parts: one dihedral reflector positioned in a slew-and-clamp mode to give the major part of the desired delay;
and a second dihedral mounted on an air-bearing carriage to provide the variable delay that is needed. After
delay, the beams exit from the vacuum and are directed by dichroic mirrors into the infrared beam-combination
and detection system. The visible light passes on to another area, to the image-tracker detectors and the
visible-light combination and detection system. The beams are combined in pupil-plane mode on beam splitters.
The combined IR beams are conveyed to two cooled single-element InSb detectors. The combined visible-light
beams are focussed by lenslet arrays onto multimode optical fibers that lead to the slit of a specially-designed
prism spectrometer. For the visible mode, the delay line is run at several wavelengths on one side of the zero-
path point, so that several cycles of interference occur across the spectrum. First results were obtained with the
IR system, giving visibilities for several K and M stars, using 2.2 micrometers radiation on a N-S baseline of
21.2 m. From these measurements we obtained preliminary estimates of effective stellar diameters in the K band.


Reference Type: Conference Proceedings
Record Number: 221
Author: Carlip, Steve
Year of Conference: 1996
Title: Gravity and Quantum Theory
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 817
Date: January 1, 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 222
Author: Carlip, S.
Year: 1998
Title: Kinetic energy and the equivalence principle
Journal: American Journal of Physics
Volume: 66
Pages: 409-413
Abstract: not available


Reference Type: Journal Article
Record Number: 223
Author: Carlip, S.
Year: 2000
Title: Aberration and the speed of gravity
Journal: Physics Letters A
Volume: 267
Pages: 81-87
Abstract: Electronic Article Available from Elsevier Science.


Reference Type: Journal Article
Record Number: 224
Author: Carusotto, S. ; Cavasinni, V. ; Mordacci, A. ; Perrone, F. ; Polacco, E. ; Iacopini, E. ; Stefanini, G.
Year: 1992
Title: Test of g universality with a Galileo type experiment
Journal: Physical Review Letters
Volume: 69
Pages: 1722-1725
Abstract: The results of an experiment searching for the difference Delta g in the free-fall acceleration of luminum and copper, in vacuum, obtained on the earth in a differential Galileo type measurement are reported. Within the sensitivity of the measurement, Delta g/g = 7.2 x 10 exp -10, no g-universality violation has been observed.


Reference Type: Journal Article
Record Number: 280
Author: Carusotto, S.; Cavasinni, V.; Mordacci, A.; Perrone, F.; Polacco, E.; Iacopini, E.; Stefanini, G.
Year: 1993
Title: Limits on the violation of g-universality with a Galileo-type experiment
Journal: Physics Letters A
Volume: 183
Pages: 355
Alternate Journal: PRL 69, 1722, 1992.
Abstract: not available


Reference Type: Journal Article
Record Number: 206
Author: Chandler, J. F. ; Babcock, R. W. ; Reasenberg, R. D. ; Shapiro, I. I.
Year: 1984
Title: New limit on G-dot
Journal: Bulletin of the American Astronomical Society
Volume: 16
Pages: 722
Abstract: not available


Reference Type: Journal Article
Record Number: 207
Author: Chandler, J. F. ; Babcock, R. W. ; Reasenberg, R. D. ; Shapiro, I. I.
Year: 1990
Title: Confirmation of the Principle of Equivalence
Journal: Bulletin of the American Astronomical Society
Volume: 22
Pages: 949
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 281
Author: Chandler, J.F.; Reasenberg, R.D.
Year of Conference: 1990
Title: POINTS: A Global Reference Frame Opportunity
Editor: Lieske, J.H.; Abalakin, V.I.
Conference Name: Inertial Coordinate System on the Sky
Publisher: Kluwer Academic Publisher, Dordrecht
Pages: 217-227
Abstract: POINTS is a space-based optical astrometric interferometer capable of measuring the angular separation of two
stars about 90 degrees apart with 5-microarcsec nominal accuracy . During the intended ten-year mission, a
repeated survey of a few hundred targets over the whole sky, including a few bright quasars, establish a 'rigid'
reference grid with 0.5 microarcsec position uncertainties. At that level, the grid is free of regional biases and
tied to the extra-Galactic frame that is the present best candidate for an inertial frame. POINTS will also
determine parallaxes and annual proper motions at about the same level. Further, the planetary ephemeris frame
is tied through stellar aberration to the grid at about 300 microarcsec. Additional targets of interest, to a limiting
magnitude of greater than 20, are observed relative to the grid, yielding determinations with uncertainties
depending on the observing schedule. Measurement at the microarcsec/year level of the apparent relative
velocities of quasars that are widely separated on the sky severely test the assumption of cosmological quasar
distances and may also constrain models of the early universe.


Reference Type: Conference Proceedings
Record Number: 282
Author: Chandler, J.F.; Reasenberg, R.D.; Shapiro, I.I.
Year of Conference: 1994
Title: Testing General Relativity with Lunar Laser Ranging
Editor: Keiser, Robert T. Jantzen and G. Mac
Conference Name: 7th Marcel Grossman Meeting
Conference Location: Stanford University
Publisher: World Scientific, Singapore
Pages: 1501
Date: 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 283
Author: Chandler, J. F.; Reasenberg, R. D.; Shapiro, I. I.
Year: 1994
Title: New results on the Principle of Equivalence
Journal: Bull. Am. Astron. Soc.
Volume: 26
Pages: 1019
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 139
Author: Chandler, John F. ; Reasenberg, Robert D. ; Shapiro, Irwin I.
Year of Conference: 1996
Title: Testing General Relativity with Lunar Laser Ranging
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 1501
Date: January 1, 1996
Abstract: not available


Reference Type: Book Section
Record Number: 284
Author: Cohen, M.R.; Drabkin, I.E.
Year: 1948
Title: A Source Book in Greek Science
Book Title: A Source Book in Greek Science
City: New York
Publisher: McGraw-Hill
Pages: 217
Abstract: not available


Reference Type: Book Section
Record Number: 131
Author: Cowsik, R. %A Krishnan, N. %A Unnikrishnan, C. S.
Year: 1999
Title: The TIFR Equivalence Principle Experiment
Book Title: Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories
Pages: 1181
Abstract: not available


Reference Type: Journal Article
Record Number: 285
Author: D'Urso, C.; Adelberger, E.G.
Year: 1997
Title: Translation of multipoles for a 1/r potential
Journal: Physical Review D
Volume: 55
Issue: 12
Pages: 7970-7972
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 225
Author: Damour, T.
Year of Conference: 1983
Title: Gravitational radiation and the motion of compact bodies
Conference Name: Gravitational Radiation
Pages: 58
Date: January 1, 1983
Abstract: Using a post-Minkowskian approximation method supplemented by a technique of asymptotic matching, the general relativistic gravitational field outside two compact bodies (neutron stars or black holes) is obtained. The equations of orbital motion of the compact bodies are deduced from the vacuum field equations by an Einstein-Infeld-Hoffman-Kerr type approach simplified by the use of complex analytic continuation. The same process of analytic continuation makes it possible to push the accuracy of the calculations up to the third order: gravitational field containing cubic nonlinearities and equations of motion deduced from the quartically non-linear vacuum Einstein equations. The equations of motion are explicitly written in Newtonian-like form as an expansion in powers of the inverse velocity of light up to the fifth order inclusively. The equations of motion up to C exp-4 are deduced from a generalized Lagrangian. The construction of Noetherian quantities conserved up to C exp-4 makes it possible to separate and investigate the C exp-5 secular kinematical effects caused by the finite velocity of propagation of gravity (Laplace-Eddington effect or 'radiation damping'). These results agree with the phenomena observed in the Hulse-Taylor pulsar PSR 1913 + 16.


Reference Type: Conference Proceedings
Record Number: 226
Author: Damour, T.
Year of Conference: 1984
Title: The motion of compact bodies and gravitational radiation
Conference Name: General Relativity and Gravitation Conference
Pages: 89-106
Date: January 1, 1984
Abstract: The problem of the gravitational interaction of two compact bodies (neutron stars or black holes) is considered. A new method is outlined where an 'external' gravitational field, obtained by iterating a post Minkowskian approximation scheme, to the field near each compact body. Equations of motion for each body are derived from the vacuum field equations by means of an Einstein-Infeld-Hoffmann-Kerr-like approach simplified by the use of complex analytic continuation. A slow motion expansion makes it possible to transform these equations into ordinary differential equations up to the second-and-a-half-post-Newtonian order. Solving the latter equations with the help of a second-post-Newtonian generalized Lagrangian, a secular acceleration of the mean orbital ongitude of each member of a gravitationally bound binary system is found. This kinematical behavior agrees with the phenomena observed in the Hulse-Taylor laser: PSR 1913+16.


Reference Type: Journal Article
Record Number: 227
Author: Damour, Thibault ; Schaefer, Gerhard
Year: 1987
Title: The two-body problem in general relativity
Journal: Academie des Sciences Paris Comptes Rendus Serie Sciences Mathematiques
Volume: 305
Pages: 839-842
Abstract: The dynamics of a system consisting of two comparable masses is studied in the second post-Newtonian approximation (at the last level where the system is still conservative). Explicit expressions for the radial period and the secular periastron advance are obtained as a function of kinetic energy and momentum. An expression for the periastron advance is then derived as a function of masses and directly observable quantities, a result which is significant in light of the high precision obtained in measurements of the binary pulsar PSR 1913+16.


Reference Type: Conference Proceedings
Record Number: 228
Author: Damour, T.
Year of Conference: 1989
Title: The Role and Use of Approximation Methods in General Relativity
Conference Name: Gravitational Magneto-Convection and Accretion
Pages: 75
Date: January 1, 1989
Abstract: not available


Reference Type: Report
Record Number: 229
Author: Damour, T.
Year: 1991
Title: General relativity and experiment: A brief review
Date: October 1, 1991
Abstract: The review concentrates on existing experimental tests of general relativity. Several solar system experiments are presently in development (GPS, POINTS, etc.), and a significant part of the efforts in the field of experimental gravitation is devoted to the construction of detectors of gravitational radiation (notably large interferometric detectors, GEO, LIGO, VIRGO, etc.).


Reference Type: Journal Article
Record Number: 230
Author: Damour, T. ; Deser, S. ; McCarthy, J.
Year: 1992
Title: Theoretical problems in nonsymmetric gravitational theory
Journal: Physical Review D
Volume: 45
Pages: 3289-
Abstract: It has recenty been noted that the nonsymmetric metric model of gravity faces severe observational constraints. We show here that it is also subject to physically unacceptable formal difficulties even as an effective field theory: When expanded about a Riemannian background, the model exhibits curvature-coupled negative-energy (ghost) modes and unacceptable asymptotic behavior.


Reference Type: Journal Article
Record Number: 231
Author: Damour, T.
Year: 1992
Title: General relativity and experiment: a brief review
Journal: Classical Quantum Gravity
Volume: 9
Pages: 55-
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Journal Article
Record Number: 232
Author: Damour, T. ; Deser, S. ; McCarthy, J.
Year: 1993
Title: Nonsymmetric gravity theories: Inconsistencies and a cure
Journal: Physical Review D
Volume: 47
Pages: 1541-1556
Abstract: Motivated by the apparent dependence of string σ models on the sum of spacetime metric and antisymmetric tensor fields, we reconsider gravity theories constructed from a nonsymmetric metric. We first show, by expanding in powers of the antisymmetric field, that all such ‘‘geometrical’’ theories homogeneous in second derivatives violate standard physical requirements: ghost freedom, absence of algebraic inconsistencies, or continuity of degree-of-freedom content. This no-go result applies in particular to the old unified theory of Einstein and its recent avatars. However, we find that the addition of nonderivative, ‘‘cosmological’’ terms formally restores consistency by giving a mass to the antisymmetric tensor field, thereby transmuting it into a fifth-force-like massive vector but with novel possible matter couplings. The resulting macroscopic models also exhibit ‘‘van der Waals’’–type gravitational effects, and may provide useful phenomenological foils to general relativity.


Reference Type: Journal Article
Record Number: 233
Author: Damour, Thibault ; Nordtvedt, Kenneth
Year: 1993
Title: Tensor-scalar cosmological models and their relaxation toward general relativity
Journal: Physical Review D
Volume: 48
Pages: 3436-3450
Abstract: Cosmological models within general tensor-multi-scalar theories of gravity are studied. By
isolating an autonomous evolution equation for the scalar fields, one shows that the expansion
of the universe during the matter-dominated era tends to drive the scalar fields toward a
minimum of the function alpha(phi) describing their coupling to matter, i.e. toward a state
where the tensor-scalar theory becomes indistinguishable from general relativity. The two
main parameters determining the efficiency of this natural attractor mechanism toward general
relativity are the redshift at the beginning of the matter era (or equivalently the present
cosmological matter density) and the curvature of the coupling function alpha(phi).
Quantitative estimates for the present level of deviation from general relativity, as measured by
the post-Newtonian parameters gamma-1, beta-1 and (G dot)/G, are derived, which give
greater significance to future improvements of solar-system gravitational tests.


Reference Type: Journal Article
Record Number: 234
Author: Damour, T. ; Esposito-Farese, G.
Year: 1993
Title: Testing for preferred-frame effects in gravity with artificial Earth satellites
Journal: Unknown
Volume: 94
Pages: 31771
Abstract: As gravity is a long-range force, one might a priori expect the Universe's global matter distribution to select a preferred rest frame for local gravitational physics. At the post-Newtonian approximation, two parameters suffice to describe the phenomenology of preferred-frame effects. It is pointed out that the observation of particular orbits of artificial Earth satellites has the potential of improving the alpha sub 1 limits by a couple of orders of magnitude, thanks to the appearance of small divisors which enhance the corresponding preferred-frame effects. There is a discrete set of inclinations which lead to arbitrarily small divisors, while, among zero-inclination (equatorial) orbits, geostationary ones are near optimal. The main alpha sub 1 - induced effects are: (1) a complex secular evolution of the eccentricity vector of the orbit, describable as the vectorial sum of several independent rotations; and (2) a yearly oscillation in the longitude of the satellite.


Reference Type: Journal Article
Record Number: 235
Author: Damour, T.
Year: 1993
Title: Strong-field tests of general relativity
Journal: Classical Quantum Gravity
Volume: 10
Pages: 59-
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Conference Proceedings
Record Number: 236
Author: Damour, T.
Year of Conference: 1995
Title: Gravitation and experiment
Conference Name: Gravitation and Quantizations, Session LVII of Les Houches
Pages: 1
Date: January 1, 1995
Abstract: Introduction Methodologies for testing theories Phenomenological approach ("compare") Theory-space approach ("contrast") Testing what? The two structural elements of general relativity New, macroscopic fields and couplings Testing the coupling of matter to an external gravitational field Experimental consequences of universal metric coupling Non-metric couplings and their observational consequences Dilaton-like couplings Multi-metric couplings, antisymmetric tensor couplings, and - local Lorentz invariance Other couplings of matter of scalar, vector, or tensor fields - and their experimental consequences Experimental results on the coupling of matter to an external - gravitational field Theoretical conclusions about the coupling of matter to an external - gravitational field Testing the Newtonian and post-Newtonian limits of metric theories - of gravity What are the most natural metric alternatives of Einstein's theory? The Newtonian limit of tensor-multi-scalar theories and its experimental - tests The post-Newtonian limit of tensor-multi-scalar theories and its - experimental tests Theoretical conclusions about weak-field, metric gravity Testing the strong and radiative gravitational field regimes Binary pulsars as laboratories for probing strong and radiative - gravitational fields Phenomenological analysis of binary-pulsar data ("parametrized - post-Keplerian formalism") Theory-space approach to binary-pulsar tests: introduction of - strong-field parameters β_{2}, β^{1}, β^{11}, ... Experimental constraints on strong-field relativistic gravity Other tests and conclusions Testing gravity on large scales Cosmological tests Other astrophysical tests and possible dark clouds Tests to come? Overall conclusions


Reference Type: Conference Proceedings
Record Number: 237
Author: Damour, Thibault
Year of Conference: 1996
Title: Was Einstein 100 Percent Right?
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 3
Date: January 1, 1996
Abstract: The confrontation between General Relativity and experimental results, notably binary pulsar
data, is summarized and its significance discussed. The agreement between experiment and
theory is numerically very impressive. However, some recent theoretical findings (existence of
non-perturbative strong-field effects, natural cosmological attraction toward zero scalar
couplings) suggest that the present agreement between Einstein's theory and experiment might
be a red herring and provide new motivations for improving the experimental tests of gravity.


Reference Type: Journal Article
Record Number: 238
Author: Damour, Thibault
Year: 1996
Title: Testing the equivalence principle: why and how?
Journal: Classical Quantum Gravity
Volume: 13
Pages: 33-A41
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Journal Article
Record Number: 286
Author: Damour, T.
Year: 1996
Title: Testing the equivalence principle: why and how?
Journal: Classical and Quantum Gravity
Volume: 13
Pages: A33-A41
Abstract: Part of the theoretical motivation for improving the present level of testing of the equivalence
principle is reviewed. The general rationale for optimizing the choice of pairs of materials to be tested is
presented. A simplified rationale is introduced based on a trichotomy of competing classes of theoretical
models.


Reference Type: Conference Proceedings
Record Number: 239
Author: Damour, Thibault
Year of Conference: 1997
Title: Gravitation and Experiment
Conference Name: Critical Problems in Physics, Proceedings of a Conference Celebrating the 250th Anniversary of Princeton University held in Princeton, NY, 31 Oct - 2 Nov, 1996. Edited by Val L. Fitch, Daniel R.Marlow, and Margit A. E. Dementi. Princeton, p.147
Pages: 147
Date: January 1, 1997
Abstract:
Introduction: Experimental tests of the coupling between matter and gravity tests of the dynamics of the gravitational field in the weak field. Regime test of the dynamics of the gravitational field in the strong field. Regime was Einstein 100% right? Discussion


Reference Type: Conference Proceedings
Record Number: 240
Author: Damour, T.
Year of Conference: 1998
Title: Experimental Tests of Relativistic Gravity
Conference Name: Abstracts of the 19th Texas Symposium on Relativistic Astrophysics and Cosmology, held in Paris, France, Dec. 14-18, 1998. Eds.: J. Paul, T. Montmerle, and E. Aubourg (CEA Saclay).
Pages: 371
Date: December 1, 1998
Abstract: A review of the present tests of relativistic gravity will be presented. Their theoretical significance will be discussed, as well as the motivation for new experiments.


Reference Type: Journal Article
Record Number: 241
Author: Damour, Thibault
Year: 2000
Title: Experimental Tests of Relativistic Gravity
Journal: Nuclear Physics B Proceedings Supplements
Volume: 80
Pages: 41-50
Abstract: The confrontation between Einstein's gravitation theory and experimental results, notably binary pulsar data, is summarized and its significance discussed. Experiment and theory agree at the 10^-3 level or better. All the basic structures of Einstein's theory (coupling of gravity matter; propagation and self-interaction of the graviattional field, including in strong field conditions) have been verified. However, the theoretical possibility that scalar couplings be naturally driven toward zero by the cosmological expansion suggests that the present agreement between Einstein's theory and experiment might be compatible with the existence of a long-range scalar contribution to gravity (such as the dilation field, or a moduli field, of string theory). This provides a new theoretical paradigm, and new motivations for improving the experimental tests of gravity


Reference Type: Conference Proceedings
Record Number: 287
Author: Dittus, H.; Greger, R.; Lochmann, S. T.; Mazilu, P.
Year of Conference: 1994
Title: Precise Experimental Free Fall Tests of the Weak Principle of Equivalence
Editor: Jantzen, Robert T.; Keiser, G. Mac; Ruffini, Remo
Conference Name: Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity,
gravitation, and relativistic field theories
Conference Location: Stanford University, 24-30 July 1994
Publisher: World Scientific
Pages: 1599
Date: 1996
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 242
Author: Dittus, H. ; Greger, R. ; Lochmann, S. T. ; Mazilu, P.
Year of Conference: 1996
Title: Precise Experimental Free Fall Tests of the Weak Principle of Equivalence
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 1599
Date: January 1, 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 243
Author: Dittus, H. ; Greger, R. ; Lochmann, St. ; Vodel, W. ; Koch, H. ; Nietzsche, S. ; von Zameck Glyscinski, J. ; Mehls, C. ; Mazilu, P.
Year: 1996
Title: Testing the weak equivalence principle at the Bremen drop tower: report on recent developments
Journal: Classical Quantum Gravity
Volume: 13
Pages: 43-A51
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Journal Article
Record Number: 288
Author: Dittus, H. ; Greger, R.; Lochmann, St.; Vodel, W.; Koch, H.; Nietzsche, S.; Glyscinski, J. von Zameck; Mehls, C.; Mazilu, P.
Year: 1996
Title: Testing the weak equivalence principle at the Bremen drop tower: report on recent developments
Journal: Class. Quantum Grav.
Volume: 13
Pages: A43-51
Abstract: The weak equivalence principle (WEP) has currently been shown to be valid to an accuracy of 5 * 10^-12. Free-fall experiments over short distances have attained an accuracy of only 5 * 10^-10.
Microgravity facilities such as the `Bremen drop tower' enable long-distance free-fall experiments which may
improve the accuracy to < 10^-12.


Reference Type: Conference Proceedings
Record Number: 289
Author: Dittus, H.; Vodel, W.; Lochmann, St.; Mehls, C.; Nietzsche, S.; Zameck Glyscinski, J. V.; Koch, H.
Year of Conference: 1998
Title: Drop Tower Tests of the Equivalence Principle
Editor: Vitale, S.
Conference Name: H0.1 Symposium of COSPAR Scientific Commission H
Conference Location: Nagoya, Japan, July 12-19, 1998
Publisher: Pergamon Press
Pages: 1237
Date: 2000
Abstract: not available


Reference Type: Journal Article
Record Number: 290
Author: Dittus, H.; Mehls, C.
Year: 2001
Title: A new experimental baseline for testing the weak equivalence principle at the Bremen drop tower
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2417-2425
Abstract: Free-fall experiments to test the weak equivalence principle are in progress at the drop tower in
Bremen. The differential acceleration of two test masses made from different materials is being measured by
means of a superconducting-quantum-interference-device- (SQUID-) based sensing technique. These
pseudo-Galilean tests are aimed at determining the Eötvös ratio to an accuracy of better than 10-12. The free-fall
height of the experimental capsules is 110 m, translating into an experimental time of about 4.5 s. The
SQUID-based sensing system guarantees a high measuring resolution of 10-12 m Hz-1/2 for the relative positions
of the test masses.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 291
Author: Dyck, H.M.; Benson, J.A.; Carleton, N.P.; Coldwell, C.; Lacasse, M.G.; Nisenson, P.; Panaysyuk, A.; Papaliolios, C.; Pearlman, M.R.; Reasenberg, R.D.; Traub, W.A.; Xu, X.; Predmore, C.R.; Schloerb, F.P.; Gibson, D.M.
Year: 1995, January
Title: First 2.2 µm Results from the IOTA Interferometer
Journal: Astronomy Journal
Volume: 109
Pages: 378-382
Abstract: We present the first infrared fringe visibility measurements made with the Infrared Optical Telescope Array on
Mt. Hopkins. Effective temperatures are derived for RX Boo, RS Cnc, and Beta Peg. RX Boo is the coolest
small-amplitude variable giant star to have an effective temperature determination. We compare the size of its
photosphere at infrared wavelengths with the sizes of its SiO and H20 radio emission regions. We also discuss
initial performance parameters for the interferometer.


Reference Type: Journal Article
Record Number: 140
Author: Faller, James E. ; Fischbach, Ephraim ; Fujii, Yasunori ; Kuroda, Kazuaki ; Paik, Ho Jung
Year: 1989
Title: Precision experiments to search for the fifth force
Journal: IEEE Transactions on Instrumentation Measurement
Volume: 38
Pages: 180-188
Abstract: Among the four known fundamental forces in nature, electromagnetism and gravity give rise to effects which extend over macroscopic distances, whereas the strong and weak forces act only over subatomic distances. It is natural to ask whether there can exist additional forces, particularly ones capable of acting over macroscopic distances in analogy to electromagnetism and gravity. This question is now the object of intense investigation both experimentally and theoretically, in the wake of recent suggestions of a possible fifth force. The theoretical motivation for such a force is reviewed, along with the current experimental situation.


Reference Type: Journal Article
Record Number: 172
Author: Faller, J. E. ; Dickey, J. O.
Year: 1990
Title: Lunar Laser Ranging
Journal: EOS Transactions
Volume: 71
Pages: 725
Abstract: not available


Reference Type: Personal Communication
Record Number: 292
Author: Faller, James
Year: 2000
Abstract: not available
Notes: private communication

Reference Type: Journal Article
Record Number: 293
Author: Finch, V.L.; Isaila, M.V.; Palmer, M.A.
Year: 1988
Title: Limits on the existance of a material-dependent intermediate-range force
Journal: Physical Review Letters
Volume: 60
Issue: 18
Pages: 1801-1804
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 141
Author: Fischbach, E.
Year of Conference: 1980
Title: Tests of General Relativity at the Quantum Level
Conference Name: NATO ASIB Proc. 58: Cosmology and Gravitation: Spin, Torsion, Rotation, and Supergravity
Pages: 359
Date: January 1, 1980
Abstract: not available


Reference Type: Journal Article
Record Number: 244
Author: Fischbach, Ephraim ; Haugan, Mark P. ; Tadic, Dubravko ; Cheng, Hai-Yang
Year: 1985
Title: Lorentz noninvariance and the Eötvös experiments
Journal: Physical Review D
Volume: 32
Pages: 154-162
Abstract: We explore the consequences of Lorentz noninvariance (LNI) for the Eötvös experiments in several models. It is shown that a violation of Lorentz invariance leads to an anomalous difference in the gravitational acceleration of two test masses which depends on their composition. Using the present experimental limits from the Eötvös experiments, we then derive a limit on the magnitude of a possible violation of Lorentz invariance in the model of Nielsen and Picek (NP). In an Appendix we present a detailed discussion of the contribution to the nuclear binding energy due to the weak interactions, which are the presumed source of the LNI effects in the NP model.


Reference Type: Journal Article
Record Number: 142
Author: Fischbach, E. ; Sudarsky, D. ; Szafer, A. ; Talmadge, C. ; Aronson, S. H.
Year: 1986
Title: Reanalysis of the Eotvos experiment
Journal: Physical Review Letters
Volume: 56
Pages: 3-6
Abstract: The results of the experiment of Eotvos, Pekar and Fekete (1922), which compared the gravitational accelerations of various materials to the earth, are reexamined, in order to find evidence of a non-Newtonian coupling Delta V(r). It is found that the Eotvos-Pekar-Fekete data are sensitive to the composition of the materials used, (Magnalium-Pt, CuSO4-Cu in solution, and tallow-Cu). The existence of an intermediate range coupling to the baryon number or hypercharge of the materials was confirmed.


Reference Type: Conference Proceedings
Record Number: 245
Author: Fischbach, E. ; Sudarsky, D. ; Szafer, A. ; Talmadge, C. ; Aronson, S. H.
Year of Conference: 1986
Title: The fifth force
Conference Name: Presented at the 23rd International Conference on High-Energy Physics, Berkeley, Calif., 16 Jul. 1986
Date: January 1, 1986
Abstract: We present a phenomenological description of the fifth force which focuses on the implications of the existing data from satellite and geophysical measurements of gravity, the Eoetvoes experiment, decays into hyperphotons, and the energy-dependence of the K(0) - anti-K(0) parameters.


Reference Type: Journal Article
Record Number: 246
Author: Fischbach, Ephraim ; Sudarsky, Daniel ; Szafer, Aaron ; Talmadge, Carrick ; Aronson, S. H.
Year: 1986
Title: Erratum: Reanalysis of the Eötvös experiment [Phys. Rev. Lett. 56, 3 (1986)]
Journal: Physical Review Letters
Volume: 56
Pages: 1427
Abstract: not available


Reference Type: Journal Article
Record Number: 247
Author: Fischbach, E. ; Sudarsky, D. ; Szafer, A. ; Talmadge, C. ; Aronson, S. H.
Year: 1986
Title: Alternative explanations of the Eötvös results
Journal: Physical Review Letters
Volume: 57
Pages: 1959
Abstract: A Comment on the Letter by Chu and Dicke, Phys. Rev. Lett. 57, (1986).


Reference Type: Journal Article
Record Number: 248
Author: Fischbach, E. ; Kloor, H. T. ; Talmadge, C. ; Aronson, S. H. ; Gillies, G. T.
Year: 1988
Title: Possibility of shielding the fifth force
Journal: Physical Review Letters
Volume: 60
Pages: 74
Abstract: A Comment on the Letter by P. Boynton et al., Phys. Rev. Lett. 59, 1385 (1987).


Reference Type: Journal Article
Record Number: 249
Author: Fischbach, Ephraim ; Talmadge, Carrick ; Krause, Dennis
Year: 1991
Title: Exponential models of non-Newtonian gravity
Journal: Physical Review D
Volume: 43
Pages: 460-467
Abstract: We show that in certain classes of theories the spatial variation of the non-Newtonian potential would be dominantly an exponential rather than a Yukawa potential, and we compare the phenomenological interpretation of the existing data in the exponential and Yukawa models. We also show that generalized forms of the exponential potential can arise naturally from simple mass spectra. Although such models cannot reconcile all of the existing data on non-Newtonian gravity, they have novel properties that can be directly studied experimentally.


Reference Type: Journal Article
Record Number: 250
Author: Fischbach, Ephraim ; Talmadge, Carrick
Year: 1992
Title: Six years of the fifth force
Journal: Nature
Volume: 356
Pages: 207-215
Abstract: Theoretical and experimental results from the search for a fifth fundamental force using the past six years are reviewed. The elementary phenomenology involved in the search for the fifth force is examined, and the results of composition-independent and composition-dependent experiments deviations from Newtonian gravity are addressed. The results elementary particle experiments are briefly discussed.


Reference Type: Journal Article
Record Number: 251
Author: Fischbach, Ephraim ; Krause, Dennis E. ; Talmadge, Carrick ; Tadic, Dubravko
Year: 1995
Title: Higher order weak interactions and the equivalence principle
Journal: Physical Review D
Volume: 52
Pages: 5417-5427
Abstract: We consider the possibility that gravity may couple anomalously to the weak interaction and thereby lead to a violation of the weak equivalence principle. It is shown that the contribution to the energy of a nucleus arising from neutrino-antineutrino exchange can be calculated rigorously, and may be the dominant contribution from higher order weak interactions. At the level of sensitivity that could be reached in the proposed STEP (satellite test of the equivalence principle) experiment, detection of an acceleration difference between the test masses could lead to new constraints on the coupling of gravity of neutrinos, and to higher-order weak interactions.


Reference Type: Conference Proceedings
Record Number: 252
Author: Fischbach, E.
Year of Conference: 1996
Title: Ten Years of the Fifth Force.
Conference Name: Dark Matter in Cosmology Quantam Measurements Experimental Gravitation
Pages: 443
Date: January 1, 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 163
Author: Fischbach, Ephraim ; Krause, Dennis E.
Year: 1999
Title: New Limits on the Couplings of Light Pseudoscalars from Equivalence Principle Experiments
Journal: Physical Review Letters
Volume: 82
Pages: 4753-4756
Abstract: The exchange of light pseudoscalar quanta between fermions leads to long-range
spin-dependent forces in order g2, where g is the pseudoscalar-fermion coupling constant. We
demonstrate that laboratory bounds on the Yukawa couplings of pseudoscalars to nucleons can
be significantly improved using results from recent equivalence principle experiments, which
are sensitive to the spin-independent long-range forces that arise in order g4 from
two-pseudoscalar exchange.


Reference Type: Journal Article
Record Number: 164
Author: Fischbach, Ephraim ; Krause, Dennis E.
Year: 1999
Title: Constraints on Light Pseudoscalars Implied by Tests of the Gravitational Inverse-Square Law
Journal: Physical Review Letters
Volume: 83
Pages: 3593-3596
Abstract: not available


Reference Type: Book
Record Number: 294
Author: Fischbach, E.; Talmadge, C.L.
Year: 1999
Title: The Search for Non-Newtonian Gravity
City: New York
Publisher: Springer-Verlag
Abstract: Newton's inverse-square law of gravitation has been one of the cornerstones of physics ever since it was
proposed 300 years ago. One of its most well known features is the prediction that all objects fall in a
gravitational field with the same acceleration. This observation, in the form of the Equivalence Principle, is a
fundamental assumption of Einstein's General Relativity Theory. This book traces the history of attempts to test
the predictions of Newtonian Gravity, and describes in detail recent experimental efforts to verify both the
inverse-square law and the Equivalence Principle. Interest in these questions have increased in recent years, as it
has become recognized that deviations from Newtonian gravity could be a signal for a new fundamental force in
nature. This is the first book devoted entirely to this subject, and will be useful to both graduate students and
researchers interested in this field. This book describes in detail the ideas that underlie searches for deviations
from the predictions of Newtonian gravity, focusing on macroscopic tests, since the question of gravitational
effects in quantum systems would warrant a separate work. A historical development is combined with detailed
technical discussions of the theoretical ideas and experimental results. A comprehensive bibliography with
approximately 450 entries is provided.


Reference Type: Journal Article
Record Number: 295
Author: Fischbach, E.; Howell, S.W.; Karunntillake, S.; Krause, D.E.; Reifenberger, R.; West, M.
Year: 2001
Title: Testing gravity in space and at ultrashort distances
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2427-2434
Abstract: In this paper we discuss experiments testing gravity in space and at ultrashort distances. We show that
the proposed STEP experiment has sufficient sensitivity to test how gravity couples to neutrinos and to
higher-order weak interactions. Then, after briefly reviewing the recent interest in ultrashort distance gravity
experiments, we describe a preliminary round of atomic force microscope (AFM) experiments which utilize the
`iso-electronic effect'. Our experimental results set new limits on proposed gravity-like forces over distance
ranges ~1-4 nm.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 296
Author: Fuligni, F.; Iafolla, V.
Year: 1997
Title: Measurement of small forces in the physics of gravitation and geophysics
Journal: Il Nuovo Cimento
Volume: 20
Issue: 5
Pages: 619-628
Abstract: not available


Reference Type: Book
Record Number: 297
Author: Goldstein
Year: 1950
Title: Classical Mechanics
City: Reading, MA
Publisher: Addison-Wesley
Abstract: not available


Reference Type: Journal Article
Record Number: 208
Author: Gundlach, J. H. ; Adelberger, E. G. ; Heckel, B. R. ; Swanson, H. E.
Year: 1996
Title: New technique for measuring Newton's constant G
Journal: Physical Review D
Volume: 54
Pages: 1256-
Abstract: We discuss a new technique for measuring Newton’s constant G using a rotating torsion
balance operated in a feedback mode. The method has several conceptually new features that
reduce sensitivity to the dominant systematic uncertainties of previous experiments. We have
successfuly conducted exploratory measurements that establish the feasibility of the new
technique.


Reference Type: Journal Article
Record Number: 209
Author: Gundlach, J. H. ; Smith, G. L. ; Adelberger, E. G. ; Heckel, B. R. ; Swanson, H. E.
Year: 1997
Title: Short-Range Test of the Equivalence Principle
Journal: Physical Review Letters
Volume: 78
Pages: 2523-2526
Abstract: We rotated a 3 ton 238U attractor around a compact torsion balance and compared the
accelerations of Cu and Pb toward U. We found that aCu-aPb = \(-0.7±5.7\)×10-13 cm/s2,
compared to the 9.8×10-5 cm/s2 gravitational acceleration toward the attractor. Our results set
new constraints on equivalence-principle violating interactions with Yukawa ranges down to 1
cm and rule out an earlier suggestion of a Yukawa interaction coupled predominantly to N-Z.


Reference Type: Journal Article
Record Number: 173
Author: Hall, John L. ; Salamon, C. ; Hils, D.
Year: 1986
Title: Phase stable lasers: progress and applications (A)
Journal: Optical Society of America Journal B Optical Physics
Volume: 3
Pages: 80
Abstract: not available


Reference Type: Journal Article
Record Number: 174
Author: Hall, John L. ; Ma, Long-Sheng ; Kramer, G.
Year: 1987
Title: Principles of optical phase-locking - Application to internal mirror He-Ne lasers phase-locked via fast control of the discharge current
Journal: IEEE Journal of Quantum Electronics
Volume: 23
Pages: 427-437
Abstract: While phase-locking techniques have long been in routine use in the microwave frequency domain, the ten-thousand-fold increase of the carrier frequency in the visible domain brings new problems for effective optical phase control. Particularly robust locks can be based on combining phase-locking under quiescent conditions with an outer frequency-control loop which takes control when phase lock is lost. Electronic strategies for implementing this process are discussed. Diagnostic techniques to allow characterization of phase-lock performance of optical oscillators are presented and discussed using as an example the phase-locking of a low-cost internal mirror He-Ne laser tube. Effectively complete phase lock was possible using small variations of the discharge current to provide fast frequency control.


Reference Type: Conference Proceedings
Record Number: 175
Author: Hall, John L.
Year of Conference: 1993
Title: Frequency-stabilized lasers: a parochial review
Conference Name: Proc. SPIE Vol. 1837, p. 2-15, Frequency Stabilized Lasers and Their Applications, Ken Y. Chung; Ed.
Volume: 1837
Pages: 2-15
Date: April 1, 1993
Abstract: It is hoped that this article will serve as a useful introduction to the art of stabilized lasers, especially for those who are joining this sport from other fields. It has become clear that pre- stabilization of the laser on the non-saturable resonance of a stable cavity is a good strategy: with adequate feedback system design, one can effectively replace the intrinsic noise of the laser with the measurement noise of the stabilizer system. By now sub-Hertz frequency control and optical phase locking have been demonstrated with most of these tunable sources. The ready access to modulation of the diode laser can lead to a very simple but impressive source, while the external stabilizer approach is attractive for dye and optically pumped solid-state sources. Current work on amplitude-stabilization of the laser pump may lead to reduction of the `intrinsic' solid state laser noise as well. With the current explosion of interest in atom trapping techniques we can look forward to major progress in the narrow-line laser/super- sharp absorber high resolution spectroscopy business. Applications range from atomic clocks to cold atom collision physics to tests of special relativity. The combination of ultra-stable lasers with cold atom interferometry will be especially powerful in offering new tests of atomic charge neutrality and of time reversal invariance via new limits on atomic electric dipole moments. Remarkably, a practical instrument for oil and gas prospecting might be based on a laser-diode/atom-interferometric measurement of local `g'.


Reference Type: Conference Proceedings
Record Number: 298
Author: Heckel, B.; Adelberger, E.; Baessler, S.; Gundlach, J.; Harris, M.; Hoyle, C.; Merkowitz, S.; Schmidt, U.; Sharp, A.; Smith, G.; Swanson, E.
Year of Conference: 1998
Title: Results on the Strong Equivalence Principle, Dark Matter, and New Forces
Editor: Vitale, S.
Conference Name: H0.1 Symposium of COSPAR Scientific Commission H
Conference Location: Nagoya, Japan, July 12-19, 1998
Publisher: Pergamon Press
Pages: 1225
Date: 2000
Abstract: Laboratory based torsion balance experiments allow sensitive tests of gravitational forces and of forces much
weaker than gravity. Our EotWash group at the University of Washington has used torsion balances to set new
limits on the equivalence principle and to probe new physics at very low energy scales. We present preliminary
results that have implications for the strong equivalence principle, the interaction of ordinary matter with dark
matter, and for limits on new forces between unpolarized and polarized matter


Reference Type: Journal Article
Record Number: 177
Author: Hils, Dieter ; Hall, J. L.
Year: 1990
Title: Improved Kennedy-Thorndike experiment to test special relativity
Journal: Physical Review Letters
Volume: 64
Pages: 1697-1700
Abstract: A modern version of the Kennedy-Thorndike experiment was carried out by searching for sidereal variations between the frequency of a laser locked to an I2 reference line and a laser locked to the resonance frequency of a highly stable cavity. No variations were found at the level of 2 x 10 to the -12th. This represents a 300-fold improvement over the original Kennedy-Thorndike experiment and allows the Lorentz transformations to be deduced entirely from experiment at an accuracy level of 70 ppm.


Reference Type: Journal Article
Record Number: 299
Author: Huber, F.M.; Messerschmid, E.W.; Smith, G.A.
Year: 2001
Title: The WEAX experiment
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2457-2466
Abstract: Einstein's weak equivalence principle (WEP) states that gravitational mass is identical to inertial
mass. This hypothesis has withstood experimental tests to an impressive accuracy of one part in 1011. Various
hypotheses based on theory and observations with matter suggest violations of WEP for antimatter may exist
anywhere from the one part in 106 to the 200% level. An observed violation at any level would have a profound
impact, e.g. it would offer an explanation as to why matter and antimatter are so distinctly separated in the
cosmos. We propose a precise test of WEP for antiprotons in microgravity. We expect to test WEP for antimatter
to about one part in 106, and foresee that additional advancements of several orders of magnitude in precision
could follow with further technical developments.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Conference Proceedings
Record Number: 300
Author: Iafolla, V.; Lorenzini, E. C.; Milyukov, V.
Year of Conference: 1997
Title: Test of the Weak Equivalence Principle in Stratospheric Free Fall
Editor: Piran, Tsvi; Ruffini, Remo
Conference Name: Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories
Conference Location: Hebrew University of Jerusalem, 22-27 June, 1997
Publisher: World Scientific Publishers
Pages: 1218
Date: 1999
Abstract: not available


Reference Type: Journal Article
Record Number: 254
Author: Iafolla, V. ; Nozzoli, S. ; Lorenzini, E. C. ; Milyukov, V.
Year: 1998
Title: Methodology and instrumentation for testing the weak equivalence principle in stratospheric free fall
Journal: Review of Scientific Instruments
Volume: 69
Pages: 4146-4151
Abstract: not available


Reference Type: Journal Article
Record Number: 145
Author: Iafolla, V. ; Mandiello, A. ; Nozzoli, S.
Year: 2000
Title: The High Sensitivity Italian Spring Accelerometer (ISA) for Fundamental Physics in Space
Journal: Advances in Space Research
Volume: 25
Pages: 1241-1244
Abstract: Many space experiments in fundamental physics require accelerometers of high sensitivity. We present here the ``Italian Spring Accelerometer'' (ISA), operating at low frequencies (10^-4 ÷ 1 Hz), whose sensitivity is expected to be better than 10^-12g / √Hz. An ISA prototype has been completed and used for ground tests. We describe ISA and report the results obtained from the experimental measurements. We have conceived a differential accelerometer based on the same physical principles as ISA which, if operated at low temperatures, could reach a sensitivity better than 10^-14g / √Hz and be of interest for testing the Weak Equivalence Principle in short-time free fall conditions


Reference Type: Journal Article
Record Number: 301
Author: Iafolla, V.; Nozzoli, S.; Lorenzini, E.C.; Shapiro, I.I.; Milyukov, V.
Year: 2000
Title: Developments of the general relativity accuracy test (GReAT): a ground-bsed experiment to test the weak equivalence principle
Journal: Classical and Quantum Gravityq
Volume: 17
Pages: 2327-2330
Abstract: not available


Reference Type: Journal Article
Record Number: 255
Author: Jafry, Y.
Year: 1996
Title: Drag-free control for MiniSTEP
Journal: Classical Quantum Gravity
Volume: 13
Pages: 179-A184
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Conference Proceedings
Record Number: 256
Author: Jafry, Yusuf
Year of Conference: 1997
Title: Overview of Mission Possibilities for Fundamental Physics in Space, and an Introduction to the Key Concepts behind Spaceborne Tests of the Weak Equivalence Principle
Conference Name: ESA SP-420: Fundamental Physics in Space
Pages: 151
Date: January 1, 1997
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 302
Author: Jafry, Y.
Year of Conference: 1997
Title: Tests of the Equivalence Principle in Space
Editor: Piran, Tsvi; Ruffini, Remo
Conference Name: Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories
Conference Location: Hebrew University of Jerusalem, 22-27 June, 1997
Publisher: World Scientific Publishers
Pages: 1207
Date: 1999
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 257
Author: Jafry, Y.
Year of Conference: 1999
Title: Tests of the Equivalence Principle in Space
Conference Name: Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories
Pages: 1207
Date: January 1, 1999
Abstract: not available


Reference Type: Report
Record Number: 258
Author: Jarnot, Monica ; Blaser, Jean-Pierre ; Everitt, Francis ; Jafry, Yusuf ; Laurance, Robin ; Nobili, Anna ; Paik, Ho Jung ; Reinhard, Ruedeger ; Rummel, Reiner ; Salmon, Jon
Year: 1993
Title: STEP: An international collaboration in fundamental physics
Date: March 1, 1993
Abstract: STEP, the Satellite Test of the Equivalence Principle, is a joint European-U.S. space program to investigate one the strangest phenomena in physics: the fact that gravity makes all bodies fall with the same acceleration. Interpreted by Isaac Newton as the outcome of an equivalence between two distinct properties of a body, weight and quantity of matter, this 'universality of free fall' was reinterpreted by Albert Einstein in terms of an even wider equivalence between the laws of physics in different accelerated reference frames, a principle which Einstein made the basis for his general theory of relativity. STEP will advance the testing of equivalence into regions where the principle may break down. It will also provide a near-ideal space laboratory for other new experiments in gravitation, elementary particle physics, and geodesy.


Reference Type: Conference Proceedings
Record Number: 303
Author: Johnston, K.J.; Seidelmann, P.K.; Reasenberg, R.D.; Babcock, R.; Phillips, J.D.
Year of Conference: 1995
Title: Newcomb Astrometric Satellite
Editor: Seidelmann, E. Hřg and K.P.
Conference Name: IAU Symposium 166 on Astronomical and Astrophysical Objectives of Sub-Milliarcsecond Optical Astrometry
Conference Location: the Hague, the Netherlands, August 15-26, 1994
Pages: 331-334
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 259
Author: Kaczmarczik, U. ; Dittus, Hansjorg ; Rath, Hans J.
Year of Conference: 1992
Title: Calibration of accelerometers on drop tower Bremen
Conference Name: ESA, Proceedings of the 8th European Symposium on Materials and Fluid Sciences in Microgravity, Volume 1 p 343-347 (SEE N94-10070 01-29)
Volume: 1
Pages: 343-347
Date: August 1, 1992
Abstract: Accuracy of accelerometer calibration under normal Earth gravity has a limit of about 0.001 m/sq s approximately equal to 0.0001 g(sub 0) in resolution (g(sub 0) acceleration of normal Earth gravity). The most important error influence is the accelerometer cross sensitivity that produces an additional bias error. Under microgravity conditions disturbing cross sensitivities can be neglected. The new ZARM (Center of Applied Space Technology and Microgravity, University of Bremen, Germany) accelerometer calibration device uses the excellent microgravity conditions of drop tower 'Bremen' to achieve better calibration accuracy. The device is specially designed to calibrate the well known quartz flexure sensors for navigation purposes. Other sensor types can be easily adapted by changing the mounting frame and the amplifier. The quality of this device will be shown by testing a high performance quartz flexure sensor (type JA 5L14).


Reference Type: Book Section
Record Number: 132
Author: Kalebin, S. M.
Year: 1996
Title: Proposals for precision experimental tests of the equivalence principle under terrestrial conditions with magnetically suspended test bodies
Book Title: Physics of Atomic Nuclei
Volume: 59
Pages: 669-674
Abstract: not available


Reference Type: Journal Article
Record Number: 374
Author: Kehagias, A. ; Sfetsos, K.
Year: 2000
Title: Deviations from the 1/r^2Newton law due to extra dimensions
Journal: Physics Letters B
Volume: 472
Pages: 39-44
Abstract: We systematically examine corrections to the gravitational inverse square law, which are due
to compactified extra dimensions. We find the induced Yukawa-type potentials for which we
calculate the strength a and range. In general the range of the Yukawa correction is given by the
wavelength of the lightest Kaluza-Klein state and its strength, relative to the standard
gravitational potential, by the corresponding degeneracy. In particular, when n extra
dimensions are compactified on an n-torus, we find that the strength of the potential is =2n,
whereas the compactification on an n-sphere gives a =n+1. For Calabi-Yau compactifications
the strength can be at most a=20.


Reference Type: Book Section
Record Number: 133
Author: Klein, W. %A Mittelstaedt, P.
Year: 1997
Title: A simple experimental demonstration of the principle of equivalence
Book Title: American Journal of Physics
Volume: 65
Pages: 316-320
Abstract: not available


Reference Type: Journal Article
Record Number: 260
Author: Krause, Dennis E. ; Fischbach, Ephraim ; Ahluwalia, D. V.
Year: 2001
Title: Testing Newtonian Gravity at Ultra-Short Distances
Journal: International Journal of Modern Physics D
Volume: 10
Pages: 25-31
Abstract: The appearance of new fundamental forces and extra-dimensional modifications to gravity in extensions of the Standard Model has motivated considerable interest in testing Newtonian gravity at ultra-short distances (<~10^-4 m). New experiments which attempt to probe these distances will encounter formidable new obstacles, including large intermolecular forces, which could obscure weak new forces or small modifications to Newton's law of gravity. Here we will review the motivation for conducting such ultra-short distance gravity experiments, and discuss some of the new problems that may arise in future experiments. Finally, we suggest a schematic design for a null experiment which would address some of these problems using the ``iso-electronic'' effect.


Reference Type: Journal Article
Record Number: 304
Author: Krisher, T.
Year: 1996
Title: Gravitational redshift in a local freely falling frame: A propsed new null test of the equivalence principle
Journal: Physical Review D
Volume: 53
Issue: 4
Pages: 1735-1739
Abstract: We consider the gravitational redshift effect measured by an observer in a local freely falling frame (LFFF) in
the gravitational field of a massive body. For purely metric theories of gravity, the metric in a LFFF is expected
to differ from that of flat spacetime by only ‘‘tidal’’ terms of order
(GM/c2R)(r′/R)2, where R is the distance of the observer from the massive body, and r′ is the
coordinate separation relative to the origin of the LFFF. A simple derivation shows that a violation of the
equivalence principle for certain types of ‘‘clocks’’ could lead to a larger apparent
redshift effect of order (1-α)(GM/c2R)(r′/R), where α parametrizes the violation (α=1
for purely metric theories, such as general relativity). Therefore, redshift experiments in a LFFF with separated
clocks can provide a new null test of the equivalence principle. With presently available technology, it is
possible to reach an accuracy of 0.01% in the gravitational field of the Sun using an atomic clock orbiting the
Earth. A 1% test in the gravitational field of the galaxy would be possible if an atomic frequency standard were
flown on a space mission to the outer solar system. (c) 1996 The American Physical Society.


Reference Type: Journal Article
Record Number: 305
Author: Kuroda, K.; Mio, N.
Year: 1990
Title: Limits on a possiblt composition-dependent force by a Galilean experiment
Journal: Phyiscs Review D
Volume: 42
Pages: 3903
Abstract: We report the details of an improved Galilean experiment involving simultaneous free fall in vacuum of
concentric masses with different compositions. This experiment is sensitive to composition-dependent
interactions between the falling masses and the Earth for forces with ranges exceeding 10 km or so that are less
accessible to torsion balance experiments. No composition dependence was observed. Limits on baryon, isospin,
and lepton couplings are presented for both Yukawa and exponential forms.


Reference Type: Conference Proceedings
Record Number: 306
Author: Lämmerzahl, C.
Year of Conference: 1997
Title: Quantum Tests of Einstein's Equivalence Principle
Editor: Piran, Tsvi; Ruffini, Remo
Conference Name: Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories
Conference Location: Hebrew University of Jerusalem, 22-27 June, 1997
Publisher: World Scientific Publishers
Pages: 1187
Date: 1999
Abstract: not available


Reference Type: Journal Article
Record Number: 307
Author: Lämmerzahl, C.; Dittus, H.; Peters, A.; Schiller, S.
Year: 2001
Title: OPTIS: a satellite-based test of special and general relativity
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2499-2508
Abstract: not available
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 375
Author: Leontaris, G. K.; Floratos, E.G.
Year: 1999
Title: Low scale unification, Newton's law and extra dimensions
Journal: Physics Letters B
Volume: 465
Pages: 95-100
Abstract: Motivated by recent work on low energy unification, in this short note we derive corrections
on Newton's inverse square law due to the existence of extra decompactified dimensions. In
the four-dimensional macroscopic limit we find that the corrections are of Yukawa type. Inside
the compactified space of n-extra dimensions the sub-leading term is proportional to the
(n+1)-power of the distance over the compactification radius ratio. Some physical
implications of these modifications are briefly discussed.


Reference Type: Journal Article
Record Number: 178
Author: Li, Z. Y.
Year: 1981
Title: The Application of Precision Time Interval Counter to Satellite Laser Ranging and Other Fields
Journal: Shanghai Observatory Annals
Volume: 3
Pages: 216
Abstract: not available


Reference Type: Journal Article
Record Number: 179
Author: Lin, Q. C. ; Yang, F. M. ; Tan, D. T. ; Tang, W. F. ; Hu, Z. Q.
Year: 1981
Title: The Preprocessing of the Satellite Laser Ranging Data
Journal: Shanghai Observatory Annals
Volume: 3
Pages: 205
Abstract: not available


Reference Type: Journal Article
Record Number: 308
Author: Lockerbie, N.A.; Veryaskin, A.V.; Xu, X.
Year: 1993
Title: Differential gravitatiojal coupling between sylindrically-symetric, concentric test masses and an arbitrary gravitational source: relevance to the STEP experiment
Journal: Classical and Quantum Gravity
Volume: 10
Pages: 2419-2430
Abstract: The gravitational interaction between a point mass and a finite, hollow, thick-walled cylinder is
calculated, the axial force is derived, and the parametric form of the coupling coefficients k2p is presented. This
theory is applied to the test-masses for the Satellite Test of the Equivalence Principle (STEP) experiment, and an
equation is derived for the differential gravitational coupling to these masses which is more than 105 times faster
to compute than a Monte-Carlo integration of similar accuracy.


Reference Type: Journal Article
Record Number: 309
Author: Lockerbie, N.A.; Xu, X.; Veryaskin, A.V.
Year: 1995
Title: Spherical harmonic representation of the gravitational coupling between a trucnated sector of a hollow sylinder and an arbitrary gravitational source: relevance to the STEP experiment
Journal: General Relativity and Gravitation
Volume: 27
Issue: 11
Pages: 1215-1229
Abstract: not available


Reference Type: Journal Article
Record Number: 310
Author: Lockerbie, N. A.; Xu, X.; Veryaskin, A. V.
Year: 1996
Title: Gravitational modelling of the test masses for STEP and LISA
Journal: Class. Quantum Grav.
Volume: 13
Pages: A91-A95
Abstract: The test masses for the proposed STEP (satellite test of the equivalence principle) experiment can
be influenced, adversely, by time-varying gravitational coupling to other masses within the spacecraft. The
liquid helium in the spacecraft's Dewar is a severe potential source of this effect, since its influence is at the
same frequency as any actual equivalence principal violation. The pairs of STEP test masses must be made
differentially immune to this effect, and a measure of this immunity can be quantified in terms of a
`differential acceleration susceptibility', defined as . Here and a are the
differential-axial and common-mode accelerations, respectively, of the two masses, for a perturbing source at
relative position . This work presents the results of analyses for STEP's test masses having either four
or six flats, included to prevent them from rolling in azimuth . Different schemes for minimizing
are discussed in detail, and it is shown that the gravitational effect of the flats may be balanced between the
inner and outer masses, leading to a `fully-balanced' pair. However, it is concluded that such a scheme is not
practical, and the `susceptibility' may be minimized, alternatively, by choosing six flats rather than four. It is
noted that the gravitational theory used here may be applied to six- or four-sided bodies, including cubic test
masses - as proposed for LISA. (I know this is an incomplete abstract because the font was incompatable, please see
http://stacks.iop.org/0264-9381/13/A91?key=nasaads.99963a5537d7e132de2031a0eb952b98 for a complete abstract.)


Reference Type: Journal Article
Record Number: 311
Author: Lockerbie, N. A.
Year: 1998
Title: The MiniSTEP Experiment
Journal: Nuclear Physics B Proceedings Supplements
Volume: 61
Pages: 3-5
Abstract: As currently conceived, the proposed MiniSTEP experiment is designed to test, with an accuracy of 1 part in
1018, the equivalence of inertial and gravitational mass. Within the experimental payload concentric pairs of test
masses, made from different materials, will be in `free fall' as they orbit around the Earth inside a drag-free
spacecraft. Any violation of the Equivalence Principle will be disclosed during the experiment by the existence
of a differential acceleration between the masses comprising each pair, as detected by SQUID-based sensors.
Four pairs of masses are to be used, each pair forming a differential accelerometer. The experiment will employ
existing space technology and cryogenic techniques in order to reach this unprecedented level of accuracy.


Reference Type: Journal Article
Record Number: 312
Author: Lockerbie, N.A.
Year: 2000
Title: A dynamical technique for measuring the gravitational qradruple coupling of the STEP and µSCOPE experimental test masses
Journal: Classical and Quantum Gravity
Volume: 17
Pages: 4195-4206
Abstract: not available


Reference Type: Journal Article
Record Number: 313
Author: Lockerbie, N.A.
Year: 2001
Title: Dynamical measurements of the gravitational qradruple coupling to experimental test masses
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2521-2531
Abstract: This paper reports and discusses the first experimental results obtained using a novel dynamical
method for measuring the inertial imbalance I/I of three reference test masses. Good agreement between
experiment and theory is found, and a measurement precision for I/I of better than one part in 104 is
demonstrated. The measured values of I/I can be converted with high sensitivity into gravitational quadrupolar
coupling, e.g. for assessing masses intended for use in equivalence principle experiments. Some future
developments for quantifying systematic error are discussed, in order to convert the current level of precision
into measurement accuracy. (this abstract is not complete because the font does not completely import, please see
http://stacks.iop.org/0264-9381/18/2521?key=nasaads.10e7b14f3d8d9713b39590c321071f0a )
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 377
Author: Long, J. C. ; Chan, H. W. ; Price, J. C.
Year: 1999
Title: Experimental status of gravitational-strength forces in the sub-centimeter regime
Journal: Nuclear Physics B
Volume: 539
Pages: 23-34
Abstract: We review the experimental constraints on additional macroscopic Yukawa forces for interaction ranges below 1 cm, and summarize several theoretical predictions of new forces in the region. An experiment using 1 kHz mechanical oscillators as test masses should be sensitive to much of the parameter space covered by the predictions.


Reference Type: Journal Article
Record Number: 314
Author: Lorenzini, E.C.; Shapiro, I.I.; Fuligini, F.; Iafolla, V.; Cosmo, M.L.; Grossi, M.D.; Cheimets, P.N.; Zielinski, J.B.
Year: 1994
Title: Test of the weak-equivalence principle in an Einstein elevator
Journal: Nuovo Cimento
Volume: 109B
Pages: 1195
Abstract: not available


Reference Type: Book Section
Record Number: 134
Author: Lyre, Holger %A Ahluwalia, D. V. %+ AA(Institut für Philosophie, Ruhr-Universität Bochum, D-44780 Bochum, Germany; holger.lyre@ruhr-uni-bochum.de), AB()
Year: 2000
Title: A Generalized Equivalence Principle
Book Title: International Journal of Modern Physics D
Volume: 9
Pages: 633-647
Abstract: Gauge field theories may quite generally be defined as describing the coupling of a matter-field to an interaction-field, and they are suitably represented in the mathematical framework of fiber bundles. Their underlying principle is the so-called gauge principle, which is based on the idea of deriving the coupling structure of the fields by satisfying a postulate of local gauge covariance. The gauge principle is generally considered to be sufficient to define the full structure of gauge-field theories. This paper contains a critique of this usual point of view: firstly, by emphazising an intrinsic gauge theoretic conventionalism which crucially restricts the conceptual role of the gauge principle and, secondly, by introducing a new generalized equivalence principle - the identity of inertial and field charge (as generalizations of inertial and gravitational mass) - in order to give a conceptual justification for combining the equations of motion of the matter-fields and the field equations of the interaction-fields.


Reference Type: Journal Article
Record Number: 180
Author: Ma, Long-Sheng ; Jungner, Peter ; Ye, Jun ; Hall, John L.
Year: 1994
Title: Delivering the same optical frequency at two places: accurate cancellation of phase noise introduced by an optical fiber or other time-varying path
Journal: Optics Letters
Volume: 19
Pages: 1777-1779
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 181
Author: Ma, Long-Sheng ; Jungner, Peter ; Ye, Jun ; Hall, John L.
Year of Conference: 1995
Title: Accurate cancellation (to milliHertz levels) of optical phase noise due to vibration or insertion phase in fiber transmitted light
Conference Name: Proc. SPIE Vol. 2378, p. 165-175, Laser Frequency Stabilization and Noise Reduction, Yaakov Shevy; Ed.
Volume: 2378
Pages: 165-175
Date: April 1, 1995
Abstract: A single-mode optical fiber is a convenient and efficient transmission medium for optical signal. However, the optical insertion phase written on the light field by the fiber is very sensitive to the surrounding environment, such as temperature or acoustic pressure. This phase-noise modulation tends to corrupt the original delta-looking Hz-level optical spectrum by broadening it toward the kilohertz domain. Here we describe a simple and effective technique for accurate cancellation of such induced phase noise, thus allowing fiber-based optical signal transmission in very demanding high-precision frequency-based applications where optical phase noise is critical the system is based on double-pass heterodyne measurement and digital phase division by two to obtain the correction signal for the phase compensating AOM. The underlying physical principle is the fact that an optical fiber path ordinarily possesses an excellent degree of linearity and reciprocity, such that two counterpropagating signals can experience the sam phase perturbations. Overall, the fiber's kilohertz level of broadening is reduced to sub-millihertz domain by our correction.


Reference Type: Journal Article
Record Number: 315
Author: Mansour, S.W.; Kuo, T.K.
Year: 1999
Title: Solar neutrinos and violation of the equivalence principle
Journal: Physical Review D
Volume: 60
Issue: 9
Pages: 1-4
Abstract: In this Brief Report, a non-standard solution to the solar neutrino problem is reexamined. This solution assumes
that neutrino flavors could have different couplings to gravity; hence, the equivalence principle is violated in this
mechanism. The gravity induced mixing has the potential of accounting for the current solar neutrino data from
several experiments even for massless neutrinos. We fit this solution to the total rate of neutrino events in the
SuperKamiokande detector (first 504 days) together with the total rate from other detectors and also with the
SuperKamiokande results for the recoil-electron spectrum.
Notes: Brief Report

Reference Type: Journal Article
Record Number: 316
Author: Marinas, N.
Year: 1999
Title: Work on a Laser Gauge to be Used for POEM (Principle of Equivalence Measurement)
Journal: American Astronomical Society Meeting 195
Volume: 88
Pages: 18
Abstract: A Galilean Equivalence Principle test is being constructed at SAO by Reasenberg and Phillips that requires a
precision distance laser gauge faster by a factor of 1000 than ones used in previous tests. A vacuum chamber
containing test masses will move along a vertical path. Each mass will have a retro-reflector used at one end
point of a laser gauge that will measure the distance between the masses. To take accurate measurements for this
experiment, the laser gauge needs a measurement capability of 0.2 nm in 10 ms. During the Summer at SAO, the
laser gauge was tested for time response and noise by obtaining a noise spectrum and calculating the 3dB
frequency of the gauge. The system also needed an increased frequency shift to allow the gauge to follow large
distance changes. By redesigning the optic path of the laser, we were able to obtain the desired frequency shift
for the experiment. This new improved system will be presented.


Reference Type: Journal Article
Record Number: 317
Author: Mester, J.; Torii, R.; Worden, P.; Lockerbie, N.; Vitale, S.; Everitt, C.W.F.
Year: 2001
Title: The STEP mission: principles and baseline design
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2475-2486
Abstract: The Satellite Test of the Equivalence Principle (STEP) will test the equality of fall of objects in Earth
orbit to an accuracy approaching one part in 108 by measuring the difference in rate of fall of test cylinders in
cryogenic differential accelerometers in a drag-free satellite. This paper describes the current baseline design
and principles used in the design of the STEP mission.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 378
Author: Michelson, Peter F. ; Price, John C. ; Taber, Robert C.
Year: 1987
Title: Resonant-mass detectors of gravitational radiation
Journal: Science
Volume: 237
Pages: 150-157
Abstract: A network of second-generation low-temperature gravitational radiation detectors is nearing completion. These detectors, sensitive to mechanical strains of order 10 to the -18th, are possible because of a variety of technical innovations that have been made in cryogenics, low-noise superconducting instrumentation, and vibration isolation techniques. Another five orders of magnitude improvement in energy sensitivity of resonant-mass detectors is possible before the linear amplifier quantum limit is encountered.


Reference Type: Journal Article
Record Number: 182
Author: Mueller, J. ; Schneider, M. ; Soffel, M. ; Ruder, H.
Year: 1991
Title: Testing Einstein's theory of gravity by analyzing Lunar Laser Ranging data
Journal: Astrophysical Journal
Volume: 382
Pages: L101-L103
Abstract: Lunar Laser Ranging data of more than 20 years have been used to accurately determine parameters of the earth-moon system (e.g., the mass of the system, the lunar tidal acceleration etc.), the station-reflector geometry, and other physical parameters like the solar quadrupole moment. In addition to these, parameters suitable for testing metric theories of gravity in the first post-Newtonian approximation have been determined with great accuracy. These are the parameterized post-Newtonian parameters gamma and beta, the Nordtvedt parameter, the geodetic precession of the lunar orbit, as well as a possible time variation of the gravitational constant.


Reference Type: Journal Article
Record Number: 183
Author: Mueller, J. ; Soffel, M.
Year: 1997
Title: Experimental Gravity and Lunar Laser Ranging.
Journal: Reviews of Modern Astronomy
Volume: 10
Pages: 191-200
Abstract: not available


Reference Type: Journal Article
Record Number: 184
Author: Mulholland, J. D.
Year: 1989
Title: The Impact of Lunar Laser Ranging on Gravitational Theory
Journal: ASTRONOMY QUARTERLY V. 6, NO. 22, P. 17, 1989
Volume: 6
Pages: 17
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 185
Author: Müller, J. ; Schneider, M. ; Söffel, M. ; Ruder, H.
Year of Conference: 1996
Title: Determination of Relativistic Quantities by Analyzing Lunar Laser Ranging Data
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 1517
Date: January 1, 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 186
Author: Müller, Jürgen ; Nordtvedt, Kenneth
Year: 1998
Title: Lunar laser ranging and the equivalence principle signal
Journal: Physical Review D
Volume: 58
Pages: 62001
Abstract: not available


Reference Type: Journal Article
Record Number: 318
Author: Nelson, P.G.; Graham, D.M.; Newman, R.D.
Year: 1990
Title: Search for an intermediate-range composition-dependent force coupling to N-Z
Journal: Physics Review D
Volume: 42
Pages: 963-976
Abstract: We report a search for composition dependence in the forces acting on two test masses made primarily of lead
and copper, due to an attracting mass made primarily of lead. The test masses are mounted on a torsion balance
of high symmetry. The attracting mass is a 320-kg lead ring in an aluminum shell, positioned so that the torsion
balance lies on the ring’s axis at a distance from its center approximately equal to &surd;3/2 times the
ring’s mean radius. When the ring is moved periodically between symmetric positions on opposite sides
of the balance, the resulting change in gravitational field experienced by the balance is spatially uniform to a very
high degree: all derivatives of the change in field at the center of the balance vanish through third order. We find
the apparent gravitational force per unit mass on the two test masses due to the attracting ring mass to be equal to
within 1.1±1.2 ppm. Assuming a parametrization of a composition-dependent force in the notation of Fischbach,
we find ξ=(5.7±6.3)×10-5 for &thetas;5=90° (N-Z coupling), ξ=(-1.2±1.3)×10-3 for &thetas;5=0° (B
coupling).


Reference Type: Journal Article
Record Number: 319
Author: Newman, R.
Year: 2001
Title: Prospects for terrestial principle test with a cryogenic torsion pendulum
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2407-2415
Abstract: A torsion pendulum may be used to measure effective differential accelerations of test masses in the
field of sources on distance scales below those accessible in a space experiment such as STEP. Operation of a
torsion pendulum at low temperature (2 K) offers many benefits, notably: low thermal noise, high fibre stability,
highly effective superconducting magnetic shielding and excellent temperature control. With such an instrument it
should be possible to detect differential accelerations as small as 10-14 cm s-2, or fractional differential
accelerations in the field of the Earth as small as n = 10-14. This paper discusses the sources of noise and
systematic error that limit a cryogenic torsion pendulum in such measurements.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 320
Author: Niebauer, T.M.; McHugh, P.M.; Faller, J.E.
Year: 1987
Title: Galilean test for the fifth force
Journal: PRL
Volume: 59
Pages: 609
Abstract: A direct free-fall experiment has been carried out to measure the differential acceleration between two different
materials (copper and uranium) falling in the earth's gravitational field. The differential acceleration was
measured to be less than 5 parts in 10 to the 10th of the normal gravitational acceleration. This null result puts
new limits on the strength and range of the proposed fifth force.


Reference Type: Journal Article
Record Number: 321
Author: Niebauer, T.M.; Sasagawa, G.S.; Faller, J.E.; Hilt, R.; Klopping, F.
Year: 1995
Title: A new generation of absolute gravimeters
Journal: Meterologia
Volume: 32
Pages: 159
Abstract: not available


Reference Type: Journal Article
Record Number: 370
Author: Nixon, G.
Year: 2001
Title: Adaptation of a Picometer Laser Distance Gauge for a Test of the Equivalence Principle
Abstract: I report on progress made toward adapting an interferometric laser distance gauge for an experimental test of the Weak Equivalence Principle. The Principle of Equivalence Measurement (POEM) being carried out by R.D. Reasenberg's Precision Astronomy Group at the Smithsonian Astrophysical Observatory will use the Smithsonian's Tracking Freguency Gauge (TFG) to measure the changes in the vertical distance between two masses in free fall for about one second. POEM intends to measure the difference, Dg, between the accelerations of the test masses to an accuracy of s(Dg)/g Ł 1 x 10 ^-13 by measuring picometer changes in the separation of the test masses. To meet POEM's requirements, the TFG is being upgraded to measure incremental distance changes during large changes in test mass separation, to measure absolute distances, and to obtain its accuracy over shorter time scales.
I have contributed to the TFG upgrade through the following:
- Retuned the TFG test bench with Harvard undergraduate Kelzie Beebe and documented procedures for fiber coupling and alignment for the TFG's qradruple-pass frequency shifter.
- Built a line driver, designed by J.D. Phillips, to incorporate the TFG's new hopping controller into the feedback loop
- Characterized the performance of the TFG frequency shifter's acousto-optic deflector-modulator (ADM) and documented its deterioration from specification
- Designed, with Phillips, a "noise-eater" servo to mitigate the effects of non-ideal ADM performance
- Demonstrated the hopping controller's ability to change its lockpoint to adjacent interference fringes, both by user command and when a fringe moves out of the frequency-shift range
- Tested absolute distance measurements for the first time with this instrument. Verified measurements of incremental distance changes.
-Characterized current performance of the TFG and identified error sources to be explored for further improvement


Reference Type: Conference Proceedings
Record Number: 322
Author: Nobili, A. M.; Bramanti, D.; Polacco, E.; Catastini, G.; Anselmi, A.; Portigliotti, S.; Lenti, A.; Severi, A.
Year of Conference: 1998
Title: The "Galileo Galilei" (GG) Project: Testing the Equivalence Principle in Space and on Earth
Editor: Vitale, S.
Conference Name: H0.1 Symposium of COSPAR Scientific Commission H
Conference Location: Nagoya, Japan, July 12-19, 1998
Publisher: Pergamon Press
Pages: 1231
Date: 2000
Abstract: not available


Reference Type: Journal Article
Record Number: 323
Author: Noecker, M.C.
Year: 1992, 18 Sept
Title: Optical Path through the imperfect cornercube
Journal: SAO Precision Astronomy Group Technical Memorandum
Volume: 92-04
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 210
Author: Noecker, Martin C. ; Phillips, James D. ; Babcock, Robert W. ; Reasenberg, Robert D.
Year of Conference: 1993
Title: Internal laser metrology for POINTS
Conference Name: Proc. SPIE Vol. 1947, p. 174-187, Spaceborne Interferometry, Robert D. Reasenberg; Ed.
Volume: 1947
Pages: 174-187
Date: September 1, 1993
Abstract: We present the designs for laser distance gauges to be used in the POINTS instrument, and preliminary performance data. For the target 5 micro-arcsecond astrometric accuracy, we must hold or monitor some critical internal dimensions of the POINTS instrument with 2 picometer (pm, 10(superscript -12) m) accuracy for a few hours. The POINTS architecture makes good use of these gauges, minimizing the number and range of dimensions that must change during operation, and maximizing the similarity of the starlight and metrology measured paths. Gauge designs have been developed for both optical-path-differencing (Michelson) and point-to-point measurements (Fabry-Perot). The Michelson fringes have been measured in a differential (comparison) test; the root-two-point variance (analogous to the Allan variance) in the difference of two measurements over essentially identical 1-meter paths was about 2 pm for averaging times between 40 seconds and 6 hours. A second design for the point-to-point measurements incorporates cornercube retro-reflectors in a resonant cavity. We discuss the new problems anticipated in this design, including the problem of maintaining laser alignment in these point-to-point gauges over the +/- 3 degree range of instrument articulation.


Reference Type: Conference Proceedings
Record Number: 324
Author: Noecker, M.C.; Murison, M.A.; Reasenberg, R.D.
Year of Conference: 1993
Title: Optic-misalignment tolerances for the POINTS interferometers
Editor: Reasenberg, R.D.
Conference Name: SPIE Conference # 1947 on Spaceborne Interferometry
Conference Location: Orlando, FL, April 14-16, 1993
Volume: 1947
Pages: 218
Date: 1993
Abstract: We present the results of two parallel studies of the sensitivity of astrometric measurements to misalignment of
each of the major optical assemblies in the POINTS instrument. Tilt and displacement of the optics lead to tilt,
displacement, and defocussing of the starlight and metrology beams, giving rise to systematic errors. In one
method, we derive analytic expressions for the lowest order dependence of the error on the misalignment, and
evaluate them in the present interferometer design. In the second method, we use a commercial numerical ray
tracing program to calculate the overall optical path travelled through the misaligned starlight and metrology
paths; from those results, our own software determines the dependence of the residual error on the original
misalignment. These sensitivities are compared to the analytic results for mutual verification. We also discuss the
impact these results have had on the design of the instrument.


Reference Type: Journal Article
Record Number: 147
Author: Nordtvedt, K.
Year: 1968
Title: Equivalence principle for massive bodies. I. Phenomenology
Journal: Physical Review
Volume: 169
Pages: 1014-1016
Abstract: not available


Reference Type: Journal Article
Record Number: 148
Author: Nordtvedt, Kenneth, Jr. ; Will, Clifford M.
Year: 1972
Title: Conservation Laws and Preferred Frames in Relativistic Gravity. II. Experimental Evidence to Rule Out Preferred-Frame Theories of Gravity
Journal: Astrophysical Journal
Volume: 177
Pages: 775
Abstract: Abstract image available at: http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972ApJ...177..775N&db_key=AST


Reference Type: Journal Article
Record Number: 149
Author: Nordtvedt, K., Jr.
Year: 1975
Title: Quantitative relationship between clock gravitational 'red-shift' violations and nonuniversality of free-fall rates in nonmetric theories of gravity
Journal: Physical Review D
Volume: 11
Pages: 245-247
Abstract: not available


Reference Type: Journal Article
Record Number: 187
Author: Nordtvedt, Kenneth
Year: 1988
Title: Lunar laser ranging and laboratory Eötvös-type experiments
Journal: Physical Review D
Volume: 37
Pages: 1070-1071
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 150
Author: Nordtvedt, Ken
Year of Conference: 1989
Title: Toward higher order tests of the gravitational interaction
Conference Name: Relativistic Gravitational Experiments in Space
Pages: 51-54
Date: August 1, 1989
Abstract: Analyses and interpretations of experiments which test post-Newtonian gravity are usually done under the assumption that gravity is a metric field phenomenon - a manifestation of space-time geometry. This, however, is unnecessary and one can start at a more primitive level - that there simply exists a phenomenological, gravitational, many-body equation of motion which must be determined by a package of observations. In fact, over the last couple decades, a diverse collection of solar system interbody tracking observations, supplemented by data from the binary pulsar system PSR 1913 + 16, has completely mapped out the first post-Newtonian order. After the fact, using empirically determined equations of motion, along with some observed properties of nongravitational clocks and rulers and conservation laws for energy, momentum and angular momentum, a post-Newtonian Lagrangian can be constructed, a geometrical space-time metric field conceptual interpretation can be developed, Lorentz invariance of the equations of motion can be shown, and the equations of motion are found to agree with the predictions of Einstein's gravitational theory, General Relativity, within experimental accuracy.


Reference Type: Journal Article
Record Number: 151
Author: Nordtvedt, Ken
Year: 1990
Title: G(dot)/G and a cosmological acceleration of gravitationally compact bodies
Journal: Physical Review Letters
Volume: 65
Pages: 953-956
Abstract: The mass of bodies with appreciable gravitational self-energy vary in time at a rate proportional to any time variation of the gravitational coupling parameter G. As a result of these mass variations, gravitationally compact bodies will experience anomalous accelerations proportional to their motion relative to the cosmological rest frame in which G = G(t). These effects alter the relationships between the rate of change of orbital period for compact bodies and the rate of change, if any, of G. The binary pulsar system PSR 1913 + 16 is consequently found to be a somewhat less sensitive probe of a possible nonzero G(dot)/G than has been suggested.


Reference Type: Journal Article
Record Number: 188
Author: Nordtvedt, Ken
Year: 1991
Title: Lunar laser ranging reexamined: The non-null relativistic contribution
Journal: Physical Review D
Volume: 43
Pages: 3131-3135
Abstract: not available


Reference Type: Journal Article
Record Number: 325
Author: Nordtvedt, Kenneth
Year: 1994
Title: Post-Newtonian gravity: its theory--experiment interface
Journal: Class. Quantum Grav.
Volume: 11
Pages: A119-A132
Abstract: The local non-gravitational physics of matter possesses, to very high degree, two observational
features: (1) cosmological constancy of its dimensionless numbers in Earth laboratories as well as
throughout spacetime, and (2) rotational invariance. This strongly implies that cosmological--gravitational
physics is metric. We review the properties of metric gravity---which represents a broad class of theories of
gravity including general relativity, a highly unique metric theory which also fulfils the strong equivalence
principle, i.e., spacetime invariance of local gravitational physics, as well. Although the more general
parametrized post-Newtonian (PPN) gravitational metric field is considered, and its empirical status is
reviewed in the appendix, particular attention is given to the most viable degrees of freedom in metric gravity
which are parametrized by two of the PPN coefficients and , both presently experimentally determined to a
part in to be in accord with general relativity's predictions. A new determination of and using existing
radar ranging data to Viking Mars landers is described which involves the simultaneous fit of two
post-Newtonian effects---Shapiro time delay of radar propagation and polarization of inner planet orbits if
the Sun's gravitational-to-inertial mass ratio differs from 1. Methods for measuring these aspects of gravity
to a part in in the future are discussed, and the special theoretical significance in reaching this precision
is outlined. Second post-Newtonian order renormalizations of first post-Newtonian order gravity effects at
the level (the Sun's fractional gravitational self-energy) are illustrated as new measurement
objectives for the future. (this is an incomplete abstract because the font does not import, please see
http://stacks.iop.org/0264-9381/11/A119?key=nasaads.9b1e3c105ddf32bc66169189c80a9929 )


Reference Type: Conference Proceedings
Record Number: 152
Author: Nordtvedt, Ken
Year of Conference: 1996
Title: The Lunar Orbit as Probe of Relativistic Gravity
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 119
Date: January 1, 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 189
Author: Nordtvedt, Kenneth
Year: 1996
Title: The isotropy of gravity from lunar laser ranging
Journal: Classical Quantum Gravity
Volume: 13
Pages: 1309-1316
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Journal Article
Record Number: 190
Author: Nordtvedt, Kenneth
Year: 1999
Title: 30 years of lunar laser ranging and the gravitational interaction
Journal: Classical Quantum Gravity
Volume: 16
Pages: 101-A112
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Journal Article
Record Number: 326
Author: Nordtvedt, K.
Year: 2000
Title: STEP's equivalence principle violating force field due to non-spherical Earth
Journal: Classical and Quantum Gravity
Volume: 17
Pages: 2531-2536
Abstract: not available


Reference Type: Journal Article
Record Number: 327
Author: Nordtvedt, K.
Year: 2001
Title: Earth's equivalence principle violating multipoles: more science from a robust violation in STEP
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2467-2473
Abstract: Because of Earth's non-sphericity, compositional inhomogeneities and crustal topography, an
equivalence principle violation seen in a STEP mission will include multipole fine structure produced by
sources effectively independent of the Earth's monopole and quantitatively different from the gravitational
multipole structure. If non-universality of gravitational free-fall occurs above STEP's detection threshold of
10-18, there is good chance (about 40%) that the monopole phenomenon will be robust - between 10-13 and 10-15
- permitting measurement of the fine structure which can yield ambiguity-breaking information about the absolute
coupling strength of the newly discovered interaction.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 328
Author: Nordtvelt, K.
Year: 1996
Title: Significance of 'second-order' light propagation experiments in the solar system
Journal: Classical and Quantum Gravity
Volume: 13
Pages: A11-A18
Abstract: New experiments designed to observe or measure the -order (second post-Newtonian)
modifications of the global speed of light function will as a matter of course also measure the -order PPN
coefficient, , to one part in or better precision. This latter achievement would perhaps be the more
scientifically significant, permitting a test of the scenario in which scalar-metric gravitational theories tend
toward (without quite reaching) pure `local' general relativity by means of the cosmologically driven
dynamics of the background scalar field(s). It is shown, independent of field theory assumptions, that any
anomaly in the spatial metric component, and consequently in the global speed of light, will quite generally
be accompanied by more easily measured -order anomalies in the same metric field component and the
speed function. (this is an incomplete abstract because the font does not import, please see
http://stacks.iop.org/0264-9381/13/A11?key=nasaads.5ddde796929ee51b72d12df2672f2585 )


Reference Type: Conference Proceedings
Record Number: 44
Author: Padilla, C.E.; Chun, H.M.; Matson, L.E.; Reasenberg, R.D.
Year of Conference: 1993
Title: Fringe-tracking filters for space-based interferometers
Editor: Reasenberg, R.D.
Conference Name: SPIE Conference # 1947 on Spaceborne Interferometry
Conference Location: Orlando, FL, April 14-16, 1993
Volume: 1947
Pages: 272
Date: 1993
Abstract: The purpose of this research is to explore, from the point of view of
nonlinear filtering, the feasibility of microarcsecond astrometry using
space-based optical interferometers in typical disturbance environments.
Two nonlinear estimators are developed to enable high precision estimates
of the optical path difference (OPD) between the two starlight paths in a
spaceborne optical interferometer. Focal plane fringe data measurements
by either CCD (charge coupled device) or photon counting (PC) cells are
processed by an Extended Kalman Filter (EKF)- based algorithm to yield
the OPD estimate. Whereas the filter based on CCD cell measurements
results in a straightforward implementation of an EKF, the filter utilizing
PC cells requires some innovations before yielding to the EKF framework.
Instead of using the photon arrival events as measurements, the filter
measurements are taken to be the interarrival time between photons. The
excellent results obtained with the PC filter are backed by intuition based
on linear analysis results. Simulation studies show that as the CCD readout
time is decreased, the performance of the CCD filter approaches that of the
PC filter.


Reference Type: Conference Proceedings
Record Number: 363
Author: Padilla, Carlos E. ; Karlov, Valeri I. ; Li, Jun ; Chun, Hon M. ; Tsitsiklis, John N. ; Reasenberg, Robert D.
Year of Conference: 1995
Title: Problem of fringe acquisition in high-precision space-based interferometers
Conference Name: Proc. SPIE Vol. 2477, p. 47-62, Spaceborne Interferometry II, Robert D. Reasenberg; Ed.
Volume: 2477
Pages: 47-62
Date: June 1, 1995
Abstract: This paper presents the results of an investigation of the problem of fringe acquisition (FA) as it applies to high-precision space-based optical interferometers. The POINTS (for Precision Optical INTerferometry in Space) instrument concept, being developed in a collaborative effort between the Smithsonian Astrophysical Observatory and the Jet Propulsion Laboratory as a wide-band space-based optical interferometer dedicated to astrometry, is used as a test baseline. In this study we analyze three candidate FA algorithms: linear correlation techniques (CT); nonlinear least squares (NLS); and, a discrete Bayes approach (DBA). Analytical methods of evaluating the probability of detection for the NLS are developed which enable a multi-parametric study of the FA problem. Among other parameters, the study examines the effects of varying the magnitude of the electronic readout noise of the focal plane detector cells (assumed to be CCD's), of increasing the bolometric magnitude of the target stars, of allowing constant drifts of the optical path difference, and of co-adding CCD cells to reduce readout noise. A signal-to-noise measure is selected that exhibits a high correlation with the FA performance and a study of the a posteriori density space reveals insight into the nonlinear nature of the interferometric measurement function. The study concludes with selected Monte Carlo simulations to confirm the analytical predictions and to compare the performance and robustness of the CT and NLS to those attainable with the DBA.


Reference Type: Conference Proceedings
Record Number: 364
Author: Padilla, Carlos E. ; Karlov, Valeri I. ; Li, Jun ; Chun, Hon M. ; Tsitsiklis, John N. ; Reasenberg, Robert D.
Year of Conference: 1995
Title: Study of fringe tracking for high-precision space-based interferometers
Conference Name: Proc. SPIE Vol. 2477, p. 63-76, Spaceborne Interferometry II, Robert D. Reasenberg; Ed.
Volume: 2477
Pages: 63-76
Date: June 1, 1995
Abstract: The purpose of the fringe tracking algorithms is to maintain lock on the target star after acquisition and to obtain the most accurate estimate possible of the scientific quantity (or quantities) of interest in the presence of dynamic disturbances to the spacecraft/interferometer ensemble. This study carries out an analysis of the performance and robustness achievable by four candidate estimation techniques when applied to an ultra-high-precision fringe tracking task (5 micro-arcsecond ultimate accuracy). The first class of fringe trackers studied include the Extended Kalman Filter. This class is followed by extensions to second and third order nonlinear filters developed by the authors. The higher order filters have expanded regions of convergence. Third, we consider the use of an invariant filter (IF) to estimate the angle between two target stars (using POINTS as a test case). The IF offers the advantage of improved robustness in the dynamical case, being in effect `invariant' to dynamics. Finally Discrete Bayes Algorithms make use of Bayes' decision rule to propagate the a posteriori distribution of the true parameter and take into account the discrete character of the Poisson photon arrival events. Variations of these algorithms, known as multiple hypotheses trackers, offer great promise for dim star tracking. An exploration of filter performance with respect to several parameters is carried out analytically and selected Monte Carlo simulations are carried out both to verify analytical predictions and to study performance.


Reference Type: Journal Article
Record Number: 329
Author: Partridge, B.
Year: 2000
Title: The universe as a laboratory for gravity
Journal: Classical and Quantum Gravity
Volume: 17
Pages: 2411-2425
Abstract: not available


Reference Type: Journal Article
Record Number: 191
Author: Pereira, S. F. ; Xiao, Min ; Kimble, H. J. ; Hall, J. L.
Year: 1988
Title: Generation of squeezed light by intracavity frequency doubling
Journal: Physical Review A
Volume: 38
Pages: 4931-4934
Abstract: Squeezed states of light are generated by the process of second-harmonic conversion within an
optical cavity resonant at both fundamental and harmonic frequencies. Observations of
squeezing are made by analyzing the spectral density of photocurrent fluctuations produced by
the total field reflected from the nonlinear cavity. Reductions in photocurrent noise of 13%
relative to the coherent-state or shot-noise level are achieved for frequency offsets near 4
MHz.


Reference Type: Conference Proceedings
Record Number: 330
Author: Phillips, J.D.; Babcock, R.W.; Chandler, J.F.; Reasenberg, R.D.
Year of Conference: 1988
Title: Tracing the Galactic Mass Distribution with Microarcsecond Astrometry
Editor: Norman, Eric
Conference Name: Workshop on Particle Astrophysics: Forefront Experimental Issues
Conference Location: Berkeley, CA, 8-10 December 1988
Publisher: World Scientific, Singapore
Date: Augut, 1989
Abstract: not available
Notes: Published as The Proceedings of the Workshop on Particle Astrophysics: Forefront Experimental Issues

Reference Type: Conference Proceedings
Record Number: 331
Author: Phillips, J.D.; Reasenberg, R.D.; Noecker, M.C.
Year of Conference: 1990
Title: Progress Report on a Picometer Null-Sensing Distance Gauge
Conference Name: JPL Workshop on Space Interferometry
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 332
Author: Phillips, J.D.; Babcock, R.W.; Murison, M.A.; Reasenberg, R.D.; Bronowicki, A.J.; Gran, M.H.; Lillie, C.F.; McKinley, W.; Zielinski, R.J.
Year of Conference: 1995
Title: Newcomb, a small astrometric interferometer
Editor: Reasenberg, R.D.
Conference Name: SPIE Conference # 2477 on Spaceborne Interferometry II
Conference Location: Orlando, FL, April 17-20, 1995
Volume: 2477
Pages: 209
Abstract: Newcomb is a design concept for a low-cost astrometric optical interferometer with nominal single-measurement
accuracy of 100 microseconds of arc ((mu) as). In a 30 month mission, it will make scientifically interesting
measurements of O-star, RR Lyrae, and Cepheid distances, probe the dark matter in our Galaxy via parallax
measurements of K giants in the disk, establish a reference grid with internal consistency better than 50
microsecond(s) , and lay groundwork for the larger optical interferometers that are expected to produce a
profusion of scientific results during the next century. With an extended mission life, Newcomb could do a useful
preliminary search for other planetary systems.


Reference Type: Conference Proceedings
Record Number: 57
Author: Phillips, J.D.; Reasenberg, R.D.
Year of Conference: 1998
Title: Optical System for an Astrometric Survey from Space
Editor: Breckinridge, P.Y. Bely and J.B
Conference Name: SPIE Conference #3356 on Space Telescopes and Instruments V
Conference Location: Kona, HI, 20-28 March 1998
Volume: 3356
Pages: 832-843
Date: 1998
Abstract: We present an optical design for a spaceborne instrument, of about half m
aperture, to perform a combined astrometic and photometric survey via a
scan similar to that of Hipparcos. A CCD detector array with time delayed
integration will permit an astrometic mission accuracy better than 50
microarcseconds for stars brighter than 10th magnitude. 1 1/2 orders better
than Hipparcos. The passband is nominally 0.4 to 0.9 microns. For the
instrument to have both high measurements rate and high accuracy, the
optical system just satisfy several requirements. It should have aberration
well under diffraction, for high precision in centroiding and as a means of
keeping unmolded shifts of the image centroids small. The system should
have a wide field of view so that there is a large overlap of successive
scans, have a large field of view for scientific throughput, and have low
image distortion so that the stellar images moved at constant rate along
columns of detector pixels. The design presented meets these requirements
using aspheric surfaces that are manufacturable. We have demonstrated that
the instrument will determine the temperature of an observed star without
requiring a dispersive element or color filters. The design is thus free of
transmissive elements, and protected from the systematic errors that they
might have induced, e.g., due to thermal variation variation and to
chromatic effects. This study was inspired by our previous consideration of
scientific throughput. Our study of data reduction from a scanning
astrometic survey mission demonstrated that there is a substantial gain in
mission accuracy if the spacecraft precesses without discontinuities such as
those that result from gas jet firings. Our study of methods of processing the
spacecraft showed that smooth rotation would be possible using solar
radiation pressure, but only if the spacecraft rotation rate were increased.
Maintaining the integration time for each object would require an optical
design of shorter focal length. Meanwhile, our study of mission accuracy as
a function of focal length showed that another increase of accuracy would
result from shorter focal length, via the greater number of lower-accuracy
measurements. Therefore we performed this optical study to find a design
with shorter focal length, having a proportionate increase in infield of
view. We conceived and investigated a family of short focal length,
wide-field designs, and developed a methodology to facilitate selection
from among them. The new baseline design achieves diffraction-limited
images over a 2.2 degree FOV with a 1.1 degree square central blockage,
and has a 7.5 m focal length.


Reference Type: Journal Article
Record Number: 192
Author: Rayman, M. D. ; Hall, John L. ; Aminoff, C. G.
Year: 1985
Title: Precise frequency synthesizer scanning of a single tunable laser using electrooptic modulation techniques (A)
Journal: J. Opt. Soc. Am. A, vol. 2, page P18
Volume: 2
Pages: 18
Abstract: not available


Reference Type: Journal Article
Record Number: 193
Author: Rayman, M. D. ; Aminoff, C. G. ; Hall, J. L.
Year: 1989
Title: Precise laser frequency scanning using frequency-synthesized optical frequency sidebands - Application to isotope shifts and hyperfine structure of mercury
Journal: Optical Society of America Journal B Optical Physics
Volume: 6
Pages: 539-549
Abstract: Based on an efficient broadband electrooptic modulator producing RF optical sidebands locked to a stable cavity, a tunable dye laser can be scanned under computer control with frequency-synthesizer precision. Cavity drift is suppressed in software by using a strong feature in the spectrum for stabilization. Mercury isotope shifts are measured with a reproducibility of about 50 kHz. This accuracy of about 1/300 of the linewidth illustrates the power of the technique. Derived hyperfine-structure constants are compared with previous atomic-beam data.


Reference Type: Journal Article
Record Number: 153
Author: Reasenberg, R. D. ; Chandler, J. F.
Year: 1984
Title: Dynamical astronomy via optical astrometric interferometry in space
Journal: Bulletin of the American Astronomical Society
Volume: 16
Pages: 723
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 29
Author: Reasenberg, R.D.
Year of Conference: 1988
Title: Internal Metrology, Key to POINTS Astrometric Accuracy
Editor: Blair, D.G.; Buckingham, M.J.
Conference Name: Fifth Marcel Grossmann Meeting
Conference Location: Perth, Australia, 8-13 August 1988
Publisher: World Scientific Publishing, Singapore
Pages: 1667-1670
Date: 1989
Abstract: We present the designs for laser distance gauges to be used in the POINTS
instrument, and preliminary performance data. For the target 5
micro-arcsecond astrometric accuracy, we must hold or monitor some
critical internal dimensions of the POINTS instrument with 2 picometer
(pm, 10(superscript -12) m) accuracy for a few hours. The POINTS
architecture makes good use of these gauges, minimizing the number and
range of dimensions that must change during operation, and maximizing the
similarity of the starlight and metrology measured paths. Gauge designs
have been developed for both optical-path-differencing (Michelson) and
point-to-point measurements (Fabry-Perot). The Michelson fringes have
been measured in a differential (comparison) test; the root-two-point
variance (analogous to the Allan variance) in the difference of two
measurements over essentially identical 1-meter paths was about 2 pm for
averaging times between 40 seconds and 6 hours. A second design for the
point-to-point measurements incorporates cornercube retro-reflectors in a
resonant cavity. We discuss the new problems anticipated in this design,
including the problem of maintaining laser alignment in these point-to-point
gauges over the +/- 3 degree range of instrument articulation


Reference Type: Journal Article
Record Number: 154
Author: Reasenberg, R. D. ; Babcock, R. W. ; Chandler, J. F. ; Gorenstein, M. V. ; Huchra, J. P. ; Pearlman, M. R. ; Shapiro, I. I. ; Taylor, R. S. ; Bender, P. ; Buffington, A. ; Carney, B. ; Hughes, J. A. ; Johnston, K. J. ; Jones, B. F. ; Matson, L. E.
Year: 1988
Title: Microarcsecond optical astrometry - an instrument and its astrophysical applications
Journal: Astronomical Journal
Volume: 96
Pages: 1731-1745
Abstract: The applications of a proposed space-based optical astrometric interferometer with a large optical bandwidth are discussed. Such an instrument would make possible an improved deflection test of general relativity, a precise and direct calibration of the Cepheid distance scale, and the determinations of stellar masses. The nominal 5-microarcsec uncertainty in the measurement of the angular separation of two stars about 90 deg apart in the sky and the projected measurement rate of 60 star pairs per day would support a range of astrophysical studies during a nominal mission life of 10 years. Means of controlling the instrument's systematic error are considered.


Reference Type: Conference Proceedings
Record Number: 333
Author: Reasenberg, R.D.; Chandler, J.F.
Year of Conference: 1988
Title: A Deflection Test with POINTS, An Astrometric Optical Interferometer in Space
Editor: Blair, D.G.; Buckingham, M.J.
Conference Name: Fifth Marcel Grossmann Meeting
Conference Location: Perth, Australia, 8-13 August, 1988
Publisher: World Scientific Publishing
Pages: 1667-1670
Date: 1989
Abstract: not available


Reference Type: Journal Article
Record Number: 212
Author: Reasenberg, R. D. ; Babcock, R. W. ; Chandler, J. F.
Year: 1989
Title: POINTS, the planet finder, II
Journal: Bulletin of the American Astronomical Society
Volume: 21
Pages: 972
Abstract: not available


Reference Type: Journal Article
Record Number: 365
Author: Reasenberg, R. D. ; Vessot, R. F. C.
Year: 1989
Title: Relativistic gravitation; Proceedings of Symposium 15 of the 27th COSPAR Plenary Meeting, Espoo, Finland, July 18-29, 1988
Journal: Advances in Space Research
Volume: 9
Abstract: Various papers on relativistic gravitation are presented. Individual topics discussed include: engineering technology for physics experiments in space, ultrastable clocks for use in space, clocks and spaceborne tests of relativistic gravitation, tests of general relativity in earth orbit using a superconducting gravity gradiometer, relativity in space astrometry projects, testing general relativity with landers on Phobos, search of gravitational waves with resonant detectors, coalescing binaries as sources of gravitational radiation, cosmic background gravitational wave radiation and prospects for its detection, antenna for laser gravitational wave observations in space, conceptual design for a Mercury relativity satellite, the black hole lens and its foci, limits on the strength of the fifth force, testing local Lorentz invariance using laboratory and space technology, quantum limitations in gravitational space experiments, research results on gravitational lenses for 1979-1988, future of experimental gravitation in space.


Reference Type: Conference Proceedings
Record Number: 366
Author: Reasenberg, R. D.
Year of Conference: 1989
Title: Optical interferometers for tests of relativistic gravity in space
Conference Name: Relativistic Gravitational Experiments in Space
Pages: 155-162
Date: August 1, 1989
Abstract: A space-based astrometric interferometer with a large optical bandwidth is considered. POINTS (Precision Optical INTerferometry in Space) would measure the angular separation of two stars separated by about 90 deg on the sky with a nominal measurement error of 5 microarcseconds (mas). For a pair of mag 10 stars, the observation would require about 10 minutes. It is estimated that the instrument would measure daily the separation of two stars for each of about 60 pairs of stars; a random sequence of such measurements, if suitably redundant, contains the closure information necessary to detect and correct time dependent measurement biases to well below the nominal measurement accuracy. The 90 deg target separation permits absolute parallax measurements in all directions. A redundant observing schedule for 300 stars and 5 quasars would provide extra redundancy to compensate for the quasars' higher magnitude. If a nominal 30-day observation sequence were repeated 4 times per year for 10 years, stellar parameter uncertainties would be obtained of: 0.6 mas, position; 0.4 mas/y, proper motion; and 0.4 mas, parallax. This set of well-observed stars and quasars would form a rigid frame and the stars would serve as reference objects for measurements of all additional targets, as well as being targets of direct scientific interest. The instrument global data analysis since objectives are considered including a relativity test and technology.


Reference Type: Conference Proceedings
Record Number: 334
Author: Reasenberg, R.D.
Year of Conference: 1990
Title: POINTS: A Small Astrometric Interferometer
Editor: M. Shao, S. Kulkarni, and D. Jones
Conference Name: JPL Workshop on Science Objectives and Architectures for Optical Interferometry in Space
Conference Location: Pasadena, CA, 12-13 March 1990
Publisher: Astrotech 21 Workshops
Volume: 1
Date: 1991, 15 May
Abstract: Newcomb is a design concept for a low-cost astrometric optical interferometer with nominal
single-measurement accuracy of 100 microseconds of arc ((mu) as). In a 30 month mission, it
will make scientifically interesting measurements of O-star, RR Lyrae, and Cepheid distances,
probe the dark matter in our Galaxy via parallax measurements of K giants in the disk,
establish a reference grid with internal consistency better than 50 microsecond(s) , and lay
groundwork for the larger optical interferometers that are expected to produce a profusion of
scientific results during the next century. With an extended mission life, Newcomb could do a
useful preliminary search for other planetary systems.


Reference Type: Conference Proceedings
Record Number: 335
Author: Reasenberg, R.D.
Year of Conference: 1990
Title: Precision Optical Interferometry in Space
Editor: Everitt, M. Demianski and F.W.F.
Conference Name: The First William Fairbank Meeting on "Relativistic Gravitational Experiments in Space"
Conference Location: Rome, 10-14 September 1990
Publisher: World Scientific Pub., Singapore
Date: 1993
Abstract: POINTS, an astrometric Optical interferometer with a nominal measurement accuracy of 5 microarcseconds for
the angle between a pair of stars separated by about 90 deg, is presently under consideration by two divisions of
NASA-OSSA. It will be a powerful new multi-disciplinary tool for astronomical research. If chosen as the
TOPS-1 (Toward Other Planetary Systems) instrument by the Solar-System Exploration Division, it will perform
a definitive search for extra-solar planetary systems, either finding and characterizing a large number of them or
showing that they are far less numerous than now believed. If chosen as the AIM (Astrometric Interferometry
Mission) by the Astrophysics Division, POINTS will open new areas of astrophysical research and change the
nature of the questions being asked in some old areas. In either case. it will be the first of a new class of
powerful instruments in space and will prove the technology for the larger members of that class to follow.
Based on a preliminary indication of the observational needs of the two missions, we find that a single POINTS
mission will meet the science objectives of both TOPS-1 and AIM. The instrument detects dispersed fringe
(channel led spectrum) and therefore can tolerate large pointing errors.


Reference Type: Conference Proceedings
Record Number: 336
Author: Reasenberg, R.D.
Year of Conference: 1990
Title: IOTA Interferometer Project: Plans, Engineering, and Laboratory Results
Editor: Breckinridge, J.B.
Conference Name: Technical Conference on Amplitude & Intensity Spatial Interferometry
Conference Location: Tucson, AZ, 14-16 February 1990
Publisher: SPIE
Volume: 1237
Pages: 128
Abstract: The Infrared-Optical Telescope Array (IOTA) is being developed by a consortium comprising Harvard
University, the MIT Lincoln Laboratory, the Smithsonian Astrophysical Observatory, the University of
Massachusetts at Amherst, and the University of Wyoming. The instrument is intended to generate high-resolution
images of astronomical objects by bringing together beams from widely separated telescopes and combining
them at a central location. The initial configuration will consist of two 0.45 m telescopes thay may range along an
L-shaped track that will permit spacings in the 5 to 38 m range, at the Smithsonian's Fred L. Whipple
Observatory on Mt. Hopkins. Initial tests of this configuration are expected to be conducted during the summer of
1991 and to yield both valuable engineering data and the first scientific results including diameters of stars and
artificial earth satellites and a measure of the extent of some circumstellar shells. The engineering data will be
applied to the refinement of IOTA, particularly to the second IOTA configuration, in which a third telescope will
be added, making it possible to obtain phase closure information.


Reference Type: Conference Proceedings
Record Number: 337
Author: Reasenberg, R.D.
Year of Conference: 1990
Title: Kalman-Filter Fringe Tracking in an Optical Interferometer
Editor: Breckinridge, J.B.
Conference Name: Technical Conference on Amplitude & Intensity Spatial Interferometry
Conference Location: Tuscon, AZ, 14-16 February 1990
Publisher: SPIE
Volume: 1237
Pages: 172
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 37
Author: Reasenberg, R.D.; Babcock, R.W.; Noecker, M.C.; J.D. Phillips, "Space-based astrometric optical interferometry with POINTS, " in The Proceedings of the ESA Colloquium on Targets for Space-Based Interferometry, European Space Agency, Beaulieu-sur-Mer, France, 13-16 October 1992, ESA Publications Division, Noordwijk, The Netherlands, ESA-SP-345, pp 59-69, December 1992.
Year of Conference: 1992
Title: Space-based astrometric optical interferometry with POINTS
Conference Name: ESA Colloquium on Targets for Space-Based Interferometry
Conference Location: European Space Agency, Beaulieu-sur-Mer, France, 13-16 October 1992
Publisher: ESA Publications Division, Noordwijk, The Netherlands
Volume: ESA-SP-345
Pages: 59-69
Date: December 1992
Abstract: POINTS, a dual space-based astrometric optical interferometer with nominal
baseline length of 2 meters and measurement accuracy of 5 microarcseconds,
which could be a powerful new multidisciplinary research tool is introduced.
The instrument, including the laser gauges which are a central aspect of the
instrument, are described. The design of the spacecraft, and the mission
operations, including the bias determination and correction, are discussed. As a
candidate for the Astrometric Interferometry Mission (AIM) mission, POINTS
could open new areas of astrophysical research and change the nature of the
questions being asked in some old areas. As a candidate for the TOPS-1
(Towards Other Planetary Systems) mission, it could be used to perform a
definitive search for extra solar planetary systems, either finding and
characterizing a large number of them or showing that they are far less
numerous than now believed. POINTS, which is small, agile, and mechanically
simple, would be the first of a new class of powerful instruments in space and
would prove the technology for the larger members of that class to follow.


Reference Type: Conference Proceedings
Record Number: 43
Author: Reasenberg, R.D.; Babcock, R.W.; Phillips, J.D.; Johnston, K.; Simon, R.
Year of Conference: 1993
Title: Newcomb, a POINTS precursor mission with scientific capacity
Editor: Reasenberg, R.D.
Conference Name: SPIE Conference # 1947 on Spaceborne Interferometry
Conference Location: Orlando, FL, April 14-16, 1993
Volume: 1947
Date: 1993
Abstract: Newcomb is a design concept for an astrometric optical interferometer
with nominal single- measurement accuracy of 100 microseconds of arc
((mu) as). In a three-year mission life, it will make scientifically interesting
measurements of O-star, RR Lyrae, and Cepheid distances, establish a
reference grid with internal consistency better than 100 (mu) as, and lay
groundwork for the larger optical interferometers that are expected to
produce a profusion of scientific results during the next century. With an
extended mission life, Newcomb could do a useful search for other
planetary systems. The instrument is a highly simplified variant of POINTS.
It has three (or four) interferometers stacked one above the other. All three
(four) optical axes lie on a great circle, which is also the nominal direction
of astrometric sensitivity. The second and third axes are separated from the
first by fixed 'observation angles' of 40.91 and 60.51 deg. The fourth axis
would be at either 70.77 or 78.60 deg from the first. Each interferometer
detects a dispersed fringe (channeled spectrum), which falls on a CCD
detector array nominally 8 k elements long and a small number of elements
wide. With a nominal baseline length of 30 cm and optical passband from
0.9 to 0.3 microns, the Nyquist limit is reached by a star +/- 21 arcmin
from the optical axis. The instrument will be constructed of stable materials
such as ULE glass, and have neither internal moving parts nor laser
metrology.


Reference Type: Journal Article
Record Number: 338
Author: Reasenberg, R.D.; Babcock, R.W.; Noecker, M.C.; Phillips, J.D.
Year: 1993
Title: POINTS: The Precision Optical INTerferometer in Space
Journal: Remote Sensing Reviews (Special Issue Highlighting the Innovative Research Program of NASA/OSSA)
Volume: 8
Pages: 69-99
Abstract: not available
Notes: J. Alexander, Guest Ed., Harwood Academic Publishers

Reference Type: Conference Proceedings
Record Number: 373
Author: Reasenberg, R.D.; R.W. Babcock; Noecker, M.C.; Phillips, J.D.
Year of Conference: 1993
Title: POINTS: The First Small Step
Editor: Reasenberg, R.D.
Conference Name: SPIE Conference # 1947 on Spaceborne Interferometry
Conference Location: Orlando, FL, April 14-16, 1993
Volume: 1947
Pages: 12
Date: 1993
Abstract: POINTS, an astrometric optical interferometer with a nominal measurement
accuracy of 5 microarcseconds for the angle between a pair of stars separated
by about 90 deg. is presently under consideration by two divisions of
NASA-OSS. Based on a preliminary indication of the observational needs of
the two missions, we find that a single POINTS mission will meet the science
objectives of both TOPS-1 and AIM. The instrument detects a dispersed fringe
(channelled spectrum) and therefore can tolerate large pointing errors. In
operation, the difficult problem of measuring the angular separation of widely
spaced star pairs is reduced to two less difficult problems: that of measuring the
angle between the two interferometers and that of measuring interferometrically
the small offset of each star from the corresponding interferometer axis. The
question of systematic error is the central theme of the instrument architecture
and the data-analysis methods. Stable materials, precise thermal control, and
continuous precise metrology are fundamental to the design of the instrument. A
preliminary version of the required picometer laser metrology has been
demonstrated in the laboratory. Post-measurement detection and correction of
time-dependent bias are the essential elements in data analysis. In that
post-measurement analysis, individual star-pair separations are combined to
determine both the relative positions of all observed stars and several instrument
parameters including overall time-dependent measurement bias. The resulting
stellar separation estimates are both global and bias-free at the level of the
uncertainty in the reduced (i.e., combined and analyzed) measurements.


Reference Type: Conference Proceedings
Record Number: 45
Author: Reasenberg, R.D.; Babcock, R.W.; Murison, M.A.; Noecker, M.C.; Phillips, J.D.; Schumaker, B.L.; Ulvestad, J.S.
Year of Conference: 1994
Title: POINTS: an astrometric spacecraft with multifarious applications
Editor: Breckinridge, J.B.
Conference Name: SPIE Conference # 2200 on Amplitude and Spatial Interferometry II
Conference Location: Kona, HI, USA, 13-18 March 1994), J.B. Breckinridge, ed., Vol. 2200, p. 2, 1994.
Volume: 2200
Pages: 2
Date: 1994
Abstract: POINTS is a dual astrometric optical interferometer with nominal baseline length
of 2 m and measurement accuracy of 5 microarcsecs for targets separated by
about 90 degrees on the sky. If selected as the ASEPS-1 mission, it could
perform a definite search for extra-solar planetary systems, either finding and
characterizing a large number of them or showing that they are far less
numerous than now believed. If selected as AIM, it could be a powerful new
multidisciplinary research tool, opening new areas of astrophysical research and
changing the nature of the questions being asked in some old areas. Based on a
preliminary indication of the observational needs of the two missions, we find
that a single POINTS mission lasting ten years would meet the science
objectives of both ASEPS-1 and AIM. POINTS, which is small, agile, and
mechanically simple, would be the first of a new class of powerful instruments
in space and would prove the technology for the larger members of the class
that are expected to follow. The instrument is designed around a metrology
system that measures both the critical distances internal to the starlight
interferometers and the angle between them. Rapid measurement leads to
closure on the sky and the ability to detect and correct time-dependent
measurement biases.


Reference Type: Conference Proceedings
Record Number: 339
Author: Reasenberg, R.D.; Babcock, R.W.; Johnston, K.J.; Phillips, J.D.; Simon, R.S.
Year of Conference: 1994
Title: Newcomb: a scientific interferometry mission at low cost
Editor: Breckinridge, J.B.
Conference Name: SPIE Conference # 2200 on Amplitude and Spatial Interferometry II
Conference Location: Kona, HI, USA, 13-18 March 1994
Volume: 2200
Pages: 18
Date: 1994
Abstract: Newcomb is a design concept for an astrometric optical interferometer with nominal single-measurement
accuracy of 100 microseconds of arc ((mu) as). In a 30-month mission life, it will make scientifically interesting
measurements of O-star, RR Lyrae, and Cepheid distances, probe the dark matter in our Galaxy via parallax
measurements of K giants in the disk, establish a reference grid with internal consistency better than 50 (mu) as,
and lay groundwork for the larger optical interferometers that are expected to produce a profusion of scientific
results during the next century. With an extended mission life, Newcomb could do a useful search for other
planetary systems.


Reference Type: Conference Proceedings
Record Number: 50
Author: Reasenberg, R.D.; Babcock, R.W.; Murison, M.A.; Noecker, M.C.; Phillips, J.D.; Schumaker, B.L.
Year of Conference: 1995
Title: POINTS: the instrument and its mission
Editor: Reasenberg, R.D.
Conference Name: SPIE Conference # 2477 on Spaceborne Interferometry II
Conference Location: Orlando, FL, April 17-20, 1995
Volume: 2477
Pages: 167-187
Abstract: POINTS comprises a pair of independent Michelson stellar interferometers and
a laser metrology system that measures both the critical starlight paths and the
angle between the two baselines. The nominal design has baselines of 2 m,
subapertures of 35 cm, and a single- measurement accuracy of 5
microarcseconds for targets separated by approximately equals 90 degree(s). In
a five-year mission, POINTS could yield, e.g., a 1% Cepheid distance scale,
galactic mass distribution, knowledge of cluster dynamics, and stellar masses
and luminosities. In a ten-year mission, POINTS could perform a deep search
for other planetary systems, using only 20% of the available observing time.
POINTS does global astrometry, i.e., it measures widely separated targets,
which yields closure calibration, numerous bright reference stars, and absolute
parallax. The instrument has only three moving-part mechanisms, and only one
of these must move with sub-milliradian accuracy. On each side of the
interferometer, there are only three (interferometrically critical) optical surfaces
preceding the beamsplitter or its fold flat. POINTS is small, agile, and
mechanically simple. It would prove much of the technology for future imaging
interferometers.


Reference Type: Patent
Record Number: 340
Author: Reasenberg, R.D.; Phillips, J.D.; Noecker, M.C.
Year: 1995, May 2
Title: System for Measuring Distance Between Two Points Using a Variable Frequency Coherent Source
Issue: US Patent 5,412,474
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 341
Author: Reasenberg, R.D.; Babcock, R.W.; Murison, M.A.; Noecker, M.C.; Phillips, J.D.; Schumaker, B.L.; Ulvestad, J.S.; McKinley, W.; Zielinski, R.J.; Lillie, C.F.
Year of Conference: 1996
Title: POINTS: High Astrometric Capacity at Modest Cost via Focused Design
Conference Name: SPIE Conference #2807 on Space Telescopes and Instruments IV
Conference Location: Denver, CO, 4-9 August 1996
Volume: 2807
Pages: 32-50
Date: 1996
Abstract: POINTS (Precision Optical INTerferometer in Space) would perform microarcsecond optical astrometric
measurements from space, yielding submicroarcsecond astrometric results from the mission. It comprises a pair
of independent Michelson stellar interferometers and a laser metrology system that measures both the critical
starlight paths and the angle between the baselines. The instrument has two baselines of 2 m, each with two
subapertures of 35 cm; by articulating the angle between the baselines, it observes targets separated by 87 to 93
deg. POINTS does global astrometry, i.e., it measures widely separated targets, which yields closure calibration,
numerous bright reference stars, and absolute parallax. Simplicity, stability, and the mitigation of systematic
error are the central design themes. The instrument has only three moving-part mechanisms, and only one of these
must move with sub-milliradian precision; and other two can tolerate a precision of several tenths of a degree.
Optical surfaces preceding the beamsplitter or its fold flat are interferometrically critical; on each side of the
interferometer, there are only three such. Thus, light loss and wavefront distortion are minimized. POINTS
represents a minimalistic design developed ab initio for space. Since it is intended for astrometry, and therefore
does not require the u-v-plane coverage of an imaging instrument, each interferometer need have only two
subapertures. The design relies on articulation of the angle between the interferometers and body pointing to
select targets; the observations are restricted to the `instrument plane.' That plane, which is fixed in the pointed
instrument, is defined by the sensitive direction for the two interferometers. Thus, there is no need for siderostats
and moving delay lines, which would have added many precision mechanisms with rolling and sliding parts that
would be required to function throughout the mission. Further, there is no need for a third interferometer, as is
required when out-of-plane observations are made. An instrument for astrometry, unlike those for imaging, can be
compact and yet scientifically productive. The POINTS instrument is compact and therefore requires no
deployment of precision structures, has no low-frequency (i.e., under 100 Hz) vibration modes, and is relatively
easy to control thermally. Because of its small size and mass, it is easily and quickly re-pointed between
observations. Further, because of the low mass, it can be economically launched into high Earth orbit which, in
conjunction with a solar shield, yields nearly unrestricted sky coverage and a stable thermal environment.


Reference Type: Conference Proceedings
Record Number: 342
Author: Reasenberg, R.D.; Babcock, R.W.; Chandler, J.F.; Phillips, J.D.
Year of Conference: 1996
Title: POINTS Mission Studies: Lessons for SIM
Editor: Soderblom, D.R.
Conference Name: Planets Beyond the Solar System and the Next Generation of Space Missions
Conference Location: Baltimore, MD, 16-18 October 1996
Publisher: Astronomical Society of the Pacific, San Francisco
Volume: 119
Pages: 191-205
Series Title: ASP Conference Series
Date: 1997
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 343
Author: Reasenberg, R.D.; Phillips, J.D.
Year of Conference: 1998
Title: Design of a Spaceborne Astrometric Survey Instrument
Editor: Breckinridge, P.Y. Bely and J.B
Conference Name: SPIE Conference #3356 on Space Telescopes and Instruments V
Conference Location: Kona, HI, 20-28 March 1998
Volume: 3356
Pages: 622-634
Date: 1998
Abstract: We have investigated the design of a small astrometric and photometric survey instrument in the Hipparcos
tradition. Such a mission will support a rich and diverse ensemble of scientific investigations. The design
objectives, which have been met in this study, are to be able to measure 10(superscript 7) stars over the full sky,
with an accuracy of 0.05 mas for mag < 9 and 20 mas for mag 15. A scanning survey instrument that uses CCD
detectors is able to measure many stars simultaneously. As compared to a pointed astrometric instrument of
comparable size, the survey instrument generally has much higher measurement throughput, but on average, less
scientific interest per target. An instrument for astrometry, unlike those for imaging, can be compact and yet
scientifically productive.


Reference Type: Conference Proceedings
Record Number: 367
Author: Reasenberg, Robert D.
Year of Conference: 1998
Title: Astronomical Interferometry
Conference Name: Proc. SPIE Vol. 3350
Volume: 3350
Date: July 1, 1998
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 368
Author: Reasenberg, R. D. ; Phillips, J. D.
Year of Conference: 2000
Title: A New Test of the Principle of Equivalence
Conference Name: AAS/Division of Dynamical Astronomy Meeting
Volume: 32
Date: May 1, 2000
Abstract: We are developing a new laboratory test, in the Galilean tradition, of the Principle of Equivalence. In this test, two samples fall in a single co-moving vacuum chamber, as their vertical separation is measured with a laser gauge. The moving system, including a small getter pump, is guided by a heavy structure, built to minimize vibration. Free-fall time is about one sec, and the system recycles in about 0.3 sec. Our preliminary objective is to measure delta-g/g with an uncertainty of 10^-11; long term, 10^-13. A detailed error budget, based on a large number of falls, supports these objectives. Once a useful accuracy is achieved, we plan to test several types of matter. The experiment will also be sensitive to intermediate-range forces, such as might result from a Yukawa potential. Since the Principle of Equivalence undergirds general relativity, an apparent violation would receive considerable interest and correspondingly severe scrutiny. This work has been supported by the Smithsonian Astrophysical Observatory.


Reference Type: Journal Article
Record Number: 369
Author: Reasenberg, Robert D. ; Phillips, James D.
Year: 2001
Title: Testing the equivalence principle on a trampoline
Journal: Classical Quantum Gravity
Volume: 18
Pages: 2435-2445
Abstract: Electronic Article Available from the Institute of Physics


Reference Type: Conference Proceedings
Record Number: 194
Author: Ricklefs, Randall L. ; Wiant, Jerry R. ; Shelus, Peter J.
Year of Conference: 1989
Title: High precision lunar tracking for laser ranging
Conference Name: Acquisition, tracking, and pointing III; Proceedings of the Meeting, Orlando, FL, Mar. 27-29, 1989 (A90-39001 17-17). Bellingham, WA, Society of Photo-Optical Instrumentation Engineers, 1989, p. 299-306.
Volume: 1111
Pages: 299-306
Date: September 1, 1989
Abstract: Laser ranging to lunar surface retroreflectors has provided a valuable source of data for the investigation of the lunar orbit, the earth's orientation in space, general relativity, and many other aspects of solar system dynamics. Due to the moon's relatively large distance, and the requirement to keep the beam from the relatively low-power laser very narrow, acquiring this data type requires very accurate telescope pointing and tracking capabilities. The nominal requirement is to keep the telescope on target within approximately 1 arcsec of its predicted location for at least several minutes. An expansion of this requirement and the methods used to accomplish this high precision pointing are presented. Difficulties encountered and a few future goals of automating the McDonald station are also discussed.


Reference Type: Journal Article
Record Number: 345
Author: Roll, P.G.; Krotkov, R.V.; Dicke, R.H.
Year: 1964
Title: The equivalence of inertial and passive gravitational mass
Journal: Annual Physics
Volume: 26
Pages: 442
Abstract: not available


Reference Type: Journal Article
Record Number: 261
Author: Romaides, Anestis J. ; Sands, Roger W. ; Eckhardt, Donald H. ; Fischbach, Ephraim ; Talmadge, Carrick L. ; Kloor, Harry T.
Year: 1994
Title: Second tower experiment: Further evidence for Newtonian gravity
Journal: Physical Review D
Volume: 50
Pages: 3608-3613
Abstract: An experimental test of the inverse-square law has been conducted on a 610 m television tower near Inverness, Mississippi. Gravity was measured at five elevations on the WABG tower, as well as on the surface within an 8 km radius surrounding the tower. These data were combined with archived data extending to 300 km, and all the surface data were corrected for terrain. Assuming the validity of the inverse-square law, the surface data were then analytically continued to predict gravity at each elevation on the tower where measurements were made. The tower observations were compared to the predictions, with the largest discrepancy being -33±30 μGal at 493 m. The results are in good agreement with previous tower experiments, which also are in accord with the inverse-square law, and they set further restrictions on possible non-Newtonian forces.


Reference Type: Conference Proceedings
Record Number: 195
Author: Rudenko, S.
Year of Conference: 1997
Title: Use of high precision Satellite Laser Ranging Data in Space Geodynamics
Conference Name: Joint European and National Astronomical Meeting
Pages: 22
Date: January 1, 1997
Abstract: Satellite laser ranging (SLR) data analysis is one of the modern techniques used to derive the Earth rotation parameters (ERP) and to establish a Terrestrial Reference Frame (TRF) realization. Information on the ERP and TRF is widely used in astrometry, geodynamics and geodesy, in particular, in the Terrestrial and Celestial Reference Frames transformation.


Reference Type: Journal Article
Record Number: 346
Author: Sampas, N.M.; Anderson, D.Z.
Year: 1990
Title: Stabilization of laser beam alignment to an optical resonator by heterodyne detection of off-axis modes
Journal: Appl. Opt.
Volume: 29
Pages: 394-403
Abstract: A method for real-time alignment of a Gaussian beam to an optical resonator is discussed. While the frequency of
a source laser is stabilized to a fundamental cavity mode resonance, phase modulation sidebands are applied at
the off-axis mode frequencies. The active laser beam position stabilization technique, as described by Grafstrom
et al. (1988), directly monitors the presence of cavity off-axis modes, indicative of misalignments, by a
heterodyne method that measures the light transmitted by the reference cavity. System performance measurements
include: (1) measurement of the quadrant detector noise; (2) calibration measurements of error signals; and (3)
open and closed loop error signal noise measurements. The feasibility of using active control of beam alignment
to suppress the coupling of an input beam has been demonstrated. Performance within a factor of 2 of the shot
noise limitation of the error signal measurement was obtained for a detected power of 160 microwatts.


Reference Type: Thesis
Record Number: 347
Author: Sampas, N.M.
Year: 1990
Title: A ring laser gyroscope with optical subtraction
Academic Dept.: Joint Institute for Laboratory Astrophysics
City: Boulder, Colorado
University: University of Colorado
Abstract: A prototype passive ring laser gyroscope uses heterodyne detection of optically derived common mode and
differential mode error signals. A 7 times 7 cm^2 ring cavity demonstrates a rotation rate sensitivity of 1.3
degrees/hr for integration periods from 1 to 30 s. Long-term sensitivity is limited by AM contamination of the
phase modulated input beams and phase drifts in the injection loop interferometer. The alignment of the injected
beams is stabilized to the reference cavity by heterodyne detection of misalignment -induced coupling to the
off-axis modes. Phase sensitive detection of partially transmitted sidebands produces error signals that are nulled
by a control system that steers the input beams. The alignment technique demonstrates sensitivities to tilts of 0.1
nrad/sqrt{ rm Hz} and to lateral beam displacements of 0.08 nm/sqrt{rm Hz} in the 1 to 1000 Hz frequency
range for a two degree-of -freedom system. Maximum alignment error suppression is 80 dB. A proposed
Earth-based experiment capable of measuring the gravitomagnetic frame-dragging effect to 1% requires a large
passive ring laser gyroscope (300 m optical path length) integrated with a long-baseline (100m) stellar
interferometer located at the South Pole.


Reference Type: Journal Article
Record Number: 348
Author: Saulson, P.
Year: 2000
Title: Interferometric gravitational wave detection: accomplishing the impossible
Journal: Classical and Quantum Gravity
Volume: 17
Pages: 2441-2448
Abstract: not available


Reference Type: Journal Article
Record Number: 166
Author: Schleef, David ; Parry, Michelle ; Tu, Shu-Ju ; Woodahl, Brian ; Fischbach, Ephraim
Year: 1999
Title: Application of geometric probability techniques to the evaluation of interaction energies arising from a general radial potential
Journal: Journal of Mathematical and Physical Sciences
Volume: 40
Pages: 1103-1112
Abstract: not available


Reference Type: Book Section
Record Number: 135
Author: Schwarzschild, Bertram
Year: 1999
Title: Gravitational self-energy and the equivalence principle
Book Title: Physics Today
Volume: 52
Pages: 19-21
Abstract: not available


Reference Type: Journal Article
Record Number: 349
Author: Selak, S.
Year: 1987
Title: Physical Background of the Principle of Equivalence
Journal: ASTROPHYSICS AND SPACE SCI.
Volume: 132
Issue: 1
Pages: 195
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 196
Author: Shelus, Peter J.
Year of Conference: 1996
Title: General Relativity Parameters: The Relevance of Lunar Laser Data From the McDonald Laser Ranging Station
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 1525
Date: January 1, 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 214
Author: Shi, X. L. ; Fu, B. ; You, S. Y. ; Ma, N. X. ; Shi, S. J.
Year: 1982
Title: Timing and Controlling Systems for the Satellite Laser Ranging System
Journal: Shanghai Observatory Annals
Volume: 4
Pages: 279
Abstract: not available


Reference Type: Journal Article
Record Number: 350
Author: Shiomi, S.; Davis, R.S.; Speake, C.C.; Mester, J.
Year: 2001
Title: Measurement of density inhomogeneities in HIPed beryllium and niobium for STEP test masses
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2533-2541
Abstract: We have determined the inhomogeneities in the density of prototype STEP test masses made from
HIPed beryllium and niobium using the hydrostatic weighing method developed at BIPM. 13 samples are taken
from a HIPed beryllium rod (approximately 140 mm long by 90 mm) and 24 samples from a niobium rod
(approximately 225 mm long by 45 mm). The maximum relative difference of density is found to be
approximately 240 ppm in the beryllium samples and 60 ppm in the niobium samples. Assuming that there is a
10 g helium bubble at 250 mm from the test masses acting as a source, these inhomogeneities of density would
produce a disturbance of a/a = (1.1±0.7)×10-18 in a beryllium outer test mass and (5.1±0.5)×10-20 in a
niobium inner test mass, in the STEP experiment. The inhomogeneities of density in the HIPed beryllium rod
appear to be too large for the STEP experiment, which aims at a sensitivity of one part in 1018. We suggest that it
is important to find a way to fabricate more homogeneous HIPed beryllium.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 351
Author: Singal, A.K.
Year: 1997
Title: The Equivalence Principle and an Electric Charge in a Gravitational Field II. A Uniformly Accelerated Charge Does Not Radiate
Journal: General Relativity and Gravitation
Volume: 29
Issue: 11
Pages: 1371-1390
Abstract: The electromagnetic field of a charge supported in a uniform gravitational field is examined from the viewpoint
of an observer falling freely in the gravitational field. It is argued that such a charge, which from the principle of
equivalence is moving with a uniform acceleration with respect to the freely falling (inertial) observer, could not
be undergoing radiation losses at a rate implied by Larmor's formula. It is explicitly shown that the total energy in
electromagnetic fields, including both velocity and acceleration fields, of a uniformly accelerated charge, at any
given instant of the inertial observer's time, is just equal to the self-energy of a non-accelerated charge moving
with a velocity equal to the instantaneous ``present'' velocity of the accelerated charge. It is further shown that at
any given instant of time, and as seen with respect to the ``present'' position of the uniformly accelerated charge,
although during the acceleration phase there is a radially outward component of the Poynting vector, there is
throughout a {\it radially inward\/} Poynting flux component during the {\it deceleration\/} phase, and a null
Poynting vector at the instant of the turn around. >From Poynting's theorem, which is defined for any region of
space strictly in terms of {\it fixed instants\/} of time, it is shown that a uniformly accelerated charge does not
emit electromagnetic radiation, in contrast to what is generally believed. It is further shown that, contrary to some
earlier suggestions in the literature, there is no continuous passing of electromagnetic radiation from a uniformly
accelerated charge into the region inaccessible to a co-accelerating observer. A comparison is made of the
electric field distributions of a supported charge versus that of a freely falling charge in a uniform gravitational
field.


Reference Type: Book Section
Record Number: 126
Author: Smith, G. L. %A Hoyle, C. D. %A Gundlach, J. H. %A Adelberger, E. G. %A Heckel, B. R. %A Swanson, H. E.
Year: 2000
Title: Short-range tests of the equivalence principle
Book Title: Physical Review D
Volume: 61
Pages: 22001
Abstract: We tested the equivalence principle at short length scales by rotating a 3 ton 238U attractor
around a compact torsion balance containing Cu and Pb test bodies. The observed differential
acceleration of the test bodies toward the attractor, aCu-aPb=(1.0±2.8)×10-13 cm/s2,
should be compared to the corresponding gravitational acceleration of 9.2×10-5 cm/s2.
Our results set new constraints on equivalence-principle violating interactions with Yukawa
ranges down to 1 cm, and improve by substantial factors existing limits for ranges between 10
km and 1000 km. Our data also set strong constraints on certain power-law potentials that can
arise from two-boson exchange processes.


Reference Type: Conference Proceedings
Record Number: 352
Author: Spallicci, Alessandro D. A. M.
Year of Conference: 1988
Title: The equivalence principle and the gravitational constant in experimental relativity
Conference Name: Italian Conference on General Relativity and Gravitational Physics, 8th
Conference Location: Cavalese, Italy, Aug. 30-Sept. 3, 1988
Publisher: World Scientific
Pages: 520-536
Date: 1989
Abstract: not available


Reference Type: Journal Article
Record Number: 167
Author: Stubbs, C. W. ; Adelberger, E. G. ; Raab, F. J. ; Gundlach, J. H. ; Heckel, B. R. ; McMurry, K. D. ; Swanson, H. E. ; Watanabe, R.
Year: 1987
Title: Search for an intermediate-range interaction
Journal: Physical Review Letters
Volume: 58
Pages: 1070-1073
Abstract: We have placed a torsion balance (containing two Be and two Cu test bodies) on a hillside to
search for intermediate-range forces that couple to baryon number. Our results constrain (at
1σ) the strength of such an interaction to be &dvbr;α˜&dvbr;≤1×10-4 for
ranges 250≤λ≤1400 m and &dvbr;α˜&dvbr;≤1×10-3 for ranges
30<λ<250 m.


Reference Type: Journal Article
Record Number: 215
Author: Su, Y. ; Heckel, B. R. ; Adelberger, E. G. ; Gundlach, J. H. ; Harris, M. ; Smith, G. L. ; Swanson, H. E.
Year: 1994
Title: New tests of the universality of free fall
Journal: Physical Review D
Volume: 50
Pages: 3614-3636
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 262
Author: Talmadge, C. ; Aronson, S. H. ; Fischbach, E.
Year of Conference: 1986
Title: Effects of local mass anomalies in Eoetvoes-like experiments
Conference Name: Presented at the 21st Recontre de Moriond, Les Arcs, Savoie, France, 26 May 1986
Date: May 1, 1986
Abstract: The effects of local mass anomalies in Eoetvoes-like experiments are considered. It is shown that in the presence of an intermediate-range non-gravitational force, the dominant contributions to both the sign and magnitude of the Eoetvoes anomaly may come from nearby masses and not from the Earth as a whole. This observation has important implications in the design and interpretation of future experiments, and in the formulation of unified theories incorporating new intermediate-range forces.


Reference Type: Journal Article
Record Number: 216
Author: Tapley, B. D. ; Schutz, B. E. ; Eanes, R. J.
Year: 1985
Title: Satellite laser ranging and its applications
Journal: Celestial Mechanics
Volume: 37
Pages: 247-261
Abstract: Satellite laser ranging (SLR) provides an important capability for precise orbit determination and for geophysical parameter estimation to support a number of contemporary geodynamic and oceanographic investigations. The precision of the SLR measurement has improved from the early meter-level systems to the current capabilities of a few centimeters for the best systems. The accuracy of the orbits and geophysical parameter recovery have shown an associated improvement. Polar motion with accuracies of 2 mas, station coordinates better than 10 cm, and interstation baseline rates indicative of tectonic motion are determined routinely with the current set of global SLR data. This discussion reviews the SLR measurement, analysis approach, and some of the recent results derived from the current SLR data set.


Reference Type: Journal Article
Record Number: 263
Author: Taylor, J. H. ; Wolszczan, A. ; Damour, Thibault ; Weisberg, J. M.
Year: 1992
Title: Experimental constraints on strong-field relativistic gravity
Journal: Nature
Volume: 355
Pages: 132-136
Abstract: Timing observations of three binary pulsars are reported which yield tight constraints on the nature of relativistic gravity in the strong-field regime. These constraints allow the measurement of velocity-dependent and nonlinear phenomena separately from the effects of gravitational radiation. General relativity is found to pass these new experimental tests with complete success.


Reference Type: Journal Article
Record Number: 353
Author: Tisdale, G.; Offerle, J.A.; Bothell, R.; Bothell, J.
Year: 1998, May
Title: Next-generation aluminum vacuum systems
Journal: Solid State Technology
Volume: 41
Pages: 79-86
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 157
Author: Touboul, P. ; Foulon, B. ; Bernard, A.
Year of Conference: 1996
Title: Servo-Controlled Accelerometers for Gravitational Experiments in Space
Conference Name: Proceedings of the Seventh Marcel Grossman Meeting on recent developments in theoretical and experimental general relativity, gravitation, and relativistic field theories
Pages: 1565
Date: January 1, 1996
Abstract: not available


Reference Type: Journal Article
Record Number: 354
Author: Touboul, P.; Rodrigues, M.; Willemenot, E.; Bernard, A.
Year: 1996
Title: Electronstatic accelerometers for the equivalence principle test in space
Journal: Classical and Quantum Gravity
Volume: 13
Pages: A67-A78
Abstract: The concept of the three-axis electrostatic accelerometers based on the full electrostatic
suspension of one unique proof mass is very suitable for space applications requiring very high resolution of
acceleration measurement or drag-free control of satellite. This concept has been tested in orbit with the
accelerometer CACTUS from ONERA in the late seventies and recently with the accelerometer ASTRE on
board Columbia shuttle in June 1996. The accelerometer outputs are derived from the measurement of the
electrostatic forces, necessary to maintain the mass motionless at the centre of the accelerometer cage. The
relative test-mass position and attitude are servo-controlled from measurements of capacitive sensors


Reference Type: Journal Article
Record Number: 355
Author: Touboul, P.; Foulon, B.; Willemenot, E.
Year: 1999
Title: Electronstatic space accelerometers for present and future missions
Journal: Acta Astronautica
Volume: 45
Issue: 10
Pages: 605-617
Abstract: not available


Reference Type: Journal Article
Record Number: 356
Author: Touboul, P.; Foulon, B.; Josselin, V.
Year: 2000
Title: Capacitive sensing and electrostatic positioning of the miniSTEP test masses
Journal: Advances in Space Research
Volume: 25
Issue: 6
Pages: 1209-1214
Abstract: The capacitive position sensing and electrostatic positioning is a multi-purpose subsystem of the miniSTEP
instrument. Implemented inside each of the four differential cryogenic accelerometers, it will be designed first to
accurately set up the position of the two test masses. In fact, all degrees of freedom of each nearly cylindrical
masses, except the rotation about the revolution axis, shall be finely controlled. The system will allow an easy
way to calibrate the SQUIDs and the superconductive magnetic suspension and to centre the two masses to satisfy
the rejection of the gravity gradient and angular motion effects. During the Equivalence Principle measurement
phase, it will provide electronic damping for the differential mode and the dither signal for the test mass charge
control system. The position measurements will be also useful for the drag compensation system of the satellite.
Taking advantage of highly accurate and low back-action sensors and of the easiness and in quite real time
adjustment of the configuration parameters through digital control loops it could even constitute a back-up for the
SQUID sensors and the magnetic bearings


Reference Type: Journal Article
Record Number: 357
Author: Touboul, P.; Rodrigues, M.
Year: 2001
Title: The MICROSCOPE space mission
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2487-2498
Abstract: The MICROSCOPE mission aims to test the equivalence principle (EP) up to an accuracy of 10-15
using its well known manifestation: the universality of free-fall. The mission, implemented in the Cnes
programme of 2000, schedules the launch of the microsatellite for 2004. The satellite payload comprises four
gravitational sensors operating at finely stabilized room temperature. The masses of the sensors are controlled to
the same orbital motion on-board the satellite, which compensates external surface forces in real time by
actuation of electrical thrusters. Accurate measurements of the electrostatic forces applied to the masses, so that
they follow the same gravitational orbit, are processed in order to reject any common effects on the masses; then
the differential outputs are observed with high precision along the Earth-pointing axis, with an expected
resolution of 5×10-15 m s-2. The quasi cylindrical test masses are concentric in order to reject gravity gradient
effects, and are made of platinum or titanium alloys. The instrument's concept and design are presented, and the
rationale of the space experiment is explained.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Conference Proceedings
Record Number: 358
Author: Traub, W.A.; Carleton, N.P.; Lacasse, M.G.; Nisenson, P.; Pearlman, M.R.; Reasenberg, R.D.; Xu, X.; Caldwell, C.M.; Panasyuk, A.; Dyck, H.M.; Benson, J.A.; Papaliolios, C.; Predmore, R.; Schloerb, F.P.
Year of Conference: 1995
Title: IOTA: Operational Status and Measurements
Editor: Schwan, P.K.
Conference Name: 1995 Space Surveillance Workshop
Publisher: Lincoln Laboratory Press, Lexington, MA
Pages: 201-208
Abstract: not available


Reference Type: Book Section
Record Number: 136
Author: Viola, Lorenza %A Onofrio, Roberto
Year: 1997
Title: Testing the equivalence principle through freely falling quantum objects
Book Title: Physical Review D
Volume: 55
Pages: 455-462
Abstract: Free fall in a uniform gravitational field is reexamined in the case of quantum states with and
without a classical analogue. The interplay between kinematics and dynamics in the evolution
of a falling quantum test particle is discussed allowing for a better understanding of the
equivalence principle at the operational level.


Reference Type: Journal Article
Record Number: 359
Author: Wang, S.; Torii, R.; Vitale, S.
Year: 2001
Title: Silica aerogel vibration testing
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2551-2559
Abstract: As has been shown in previous experiments (Dolesi R et al 2000 J. Low Temp. Phys. 118 219), a
porous silica aerogel network can adequately constrain on-orbit motion of superfluid helium, and subsequently
remove the possibility of a `helium tide' gravitational disturbance appearing in the Satellite Test of the
Equivalence Principle (STEP) signal bandwidth. Silica aerogel is used to decouple the superfluid helium from
the Earth (STEP source field). This paper addresses two key issues for flight implementation. The first is to see
whether the litre size samples of aerogel needed to fill the flight Dewar behave significantly differently to the
millilitre size samples that have been extensively studied in the literature. We have found no significant
difference. The second issue is to see whether silica aerogel filled with superfluid helium will survive launch.
Based on the tests reported here, we have found no intrinsic property of the silica aerogel/superfluid helium
system that would cause it to fail in a launch environment.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 217
Author: Watanabe, R. ; Stubbs, C. W. ; Adelberger, E. G.
Year: 1988
Title: Shielding the ``fifth force''?
Journal: Physical Review Letters
Volume: 61
Pages: 2152
Abstract: not available


Reference Type: Journal Article
Record Number: 198
Author: Wilkins, G. A.
Year: 1983
Title: Satellite Laser Ranging
Journal: GEMINI Newsletter Royal Greenwich Observatory
Volume: 7
Pages: 1
Abstract: not available


Reference Type: Book
Record Number: 360
Author: Will, C.M.
Year: 1993
Title: Theory and Experiment in Gravitational Physics
Publisher: Cambridge University Press
Edition: 2nd
Abstract: not available


Reference Type: Journal Article
Record Number: 199
Author: Williams, J. G. ; Newhall, X. X. ; Dickey, J. O.
Year: 1996
Title: Relativity parameters determined from lunar laser ranging
Journal: Physical Review D
Volume: 53
Pages: 6730-6739
Abstract: not available


Reference Type: Journal Article
Record Number: 200
Author: Wong, N. C. ; Hall, John L.
Year: 1985
Title: Servo control of amplitude modulation in frequency-modulation spectroscopy: demonstration of shot-noise-limited detection
Journal: Optical Society of America Journal B Optical Physics
Volume: 2
Pages: 1527-1534
Abstract: not available


Reference Type: Journal Article
Record Number: 201
Author: Wong, N. C. ; Hall, John L.
Year: 1986
Title: High-performance laser frequency stabilization using an external electrooptic phase shifter (A)
Journal: J. Opt. Soc. Am. A, vol. 3, page P120
Volume: 3
Pages: 120
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 159
Author: Worden, P. W., Jr.
Year of Conference: 1976
Title: Equivalence principle tests in earth orbit
Conference Name: Anaheim International Astronautical Federation Congress
Date: October 1, 1976
Abstract: An analysis of experiments which test the uniqueness of the ratio of inertial and passive gravitational mass has been made. The analysis shows that an improvement in sensitivity of at least six orders of magnitude is possible in earth orbit. The optimum experiment compares the rate of fall of two independent test bodies in a cryogenic environment aboard a drag-free satellite; this 'free fall' experiment is very much less sensitive to gravity gradient than a torsion balance. The dominant noise sources for such an experiment are expected to be gravity gradients, tracking errors, and gas pressure effects; thermal noise is not a limiting factor. A laboratory version of the experiment is under test; preliminary results are described.


Reference Type: Journal Article
Record Number: 160
Author: Worden, S.
Year: 1978
Title: Speckle interferometry
Journal: New Scientist
Volume: 78
Pages: 238-240
Abstract: It is noted that atmospheric twinkling (or 'seeing') limits the resolution obtainable from ground-based telescopes. The limit of angular resolution is inversely proportional to the diameter of the main light collector. Turbulence in the earth's atmosphere degrades this angular resolution. In order to rectify this problem, multiple-aperture interferometers, consisting of a large number of images superimposed on each other, have been used. These 'speckled' images may be analyzed with Fourier mathematics and Fourier processing. The methods have been used for studying binary stars and for determining the sizes of asteroids and the sun. A technique has also been developed for reconstructing actual images of Betelgeuse, the red star in the shoulder of the Orion constellation. It is based on computer processing data on individual speckles in a series of images. In the future speckle size determinations will be extended to quasars and exploding galactic nuclei.


Reference Type: Journal Article
Record Number: 361
Author: Worden, Paul W.; Everitt, C. W. Francis; Bye, M.
Year: 1989
Title: The Stanford equivalence principle program
Journal: NASA, Relativistic Gravitational Experiments in Space
Pages: 137-140
Abstract: The Stanford Equivalence Principle Program (Worden, Jr. 1983) is intended to test the uniqueness of free fall to
the ultimate possible accuracy. The program is being conducted in two phases: first, a ground-based version of
the experiment, which should have a sensitivity to differences in rate of fall of one part in 1012; followed by an
orbital experiment with a sensitivity of one part in 1017 or better. The ground-based experiment, although a
sensitive equivalence principle test in its own right, is being used for technology development for the orbital
experiment. A secondary goal of the experiment is a search for exotic forces. The instrument is very well suited
for this search, which would be conducted mostly with the ground-based apparatus. The short range predicted for
these forces means that forces originating in the Earth would not be detectable in orbit. But detection of
Yukawa-type exotic forces from a nearby large satellite (such as Space Station) is feasible, and gives a very
sensitive and controllable test for little more effort than the orbiting equivalence principle test itself.


Reference Type: Journal Article
Record Number: 362
Author: Worden, P.; Mester, J.; Torri, R.
Year: 2001
Title: STEP error model development
Journal: Classical and Quantum Gravity
Volume: 18
Issue: 13
Pages: 2543-2550
Abstract: We describe the ongoing development of a comprehensive error model for the satellite test of the
equivalence principle, STEP. The goal is to employ a model of the experiment and apparatus as a self-consistent
whole. The model uses a set of input parameters based on experiment design and the measured characteristics of
STEP sensor systems. The output of the model evaluates specific disturbances to the test masses in the general
categories of thermal noise, gas pressure forces, electrical forces, magnetic forces, gravitational forces, radiation
pressure and vibration. Use of the model to set experiment requirements and to evaluate design trade-offs are
briefly discussed.
Notes: Proceedings of the International Symposium on Testing the Equivalence Principle in Space, N.A. Lockerbie, Guest Ed.

Reference Type: Journal Article
Record Number: 202
Author: Xia, H. R. ; Cirac, J. I. ; Swartz, S. ; Kohler, B. ; Elliott, D. S. ; Hall, John L. ; Zoller, P.
Year: 1994
Title: Phase shifts and intensity dependence in frequency-modulation spectroscopy
Journal: Optical Society of America Journal B Optical Physics
Volume: 11
Pages: 721-730
Abstract: not available


Reference Type: Conference Proceedings
Record Number: 203
Author: Ye, Jun ; Ma, Long Sheng ; Hall, John L.
Year of Conference: 1998
Title: Cavity-enhanced frequency modulation spectroscopy: advancing optical detection sensitivity and laser frequency stabilization
Conference Name: Proc. SPIE Vol. 3270, p. 85-96, Methods for Ultrasensitive Detection, Bryan L. Fearey; Ed.
Volume: 3270
Pages: 85-96
Date: May 1, 1998
Abstract: High detection sensitivities of quantum absorptions are important in many research fields of physics, chemistry and biology. In this paper we present our latest results on the ultrasensitive molecular overtone spectroscopy using the cavity-enhanced frequency modulation (FM) technique. The principle of this method makes use of a high-finesse external cavity to enhance the intrinsic resonance contrast, while an FM modulation approach provides short-noise limited signal recovery. Ideal matching of the FM sideband frequency to the cavity free-spectral-range makes the detection process insensitive to laser frequency noise relative noise relative to the cavity, while at the same time overcomes the cavity bandwidth limit.Working with a 1064-nm Nd:YAG laser, we have obtained sub-Doppler overtone resonances of HCCD, HCCH and CO₂ molecules. A detection sensitivity of 5 X 10^-13 of integrated absorption over 1-s averaging time has been achieved. The resultant high signal- to-noise ratio of the weak resonance produces excellent laser frequency stabilization.


Reference Type: Journal Article
Record Number: 204
Author: Ye, Jun ; Hall, John L. ; Diddams, Scott A.
Year: 2000
Title: Precision phase control of an ultrawide-bandwidth femtosecond laser: a network of ultrastable frequency marks across the visible spectrum
Journal: Optics Letters
Volume: 25
Pages: 1675-1677
Abstract: not available


Reference Type: Journal Article
Record Number: 205
Author: Zhou, Y. F.
Year: 1985
Title: The Developing Lunar Laser Ranging Systems
Journal: Publications of the Yunnan Observatory
Volume: 2
Pages: 101
Abstract: not available