Graduate seminar on topical areas in modern astrophysics and
cosmology. Each semester a different topic of current special
interest is selected. Participants in this seminar discuss papers
given by seminar members (in rotation). Several faculty members also
participate.
Note: Participation for three semesters is required to obtain
credit for this course.
J. A. Peacock "Clustering of Mass and
Galaxies" (astro-ph/0002013)
I will end with a brief history of redshift surveys, both pencil-beam
and large-area local surveys. I compare the "faint end slopes" of the
galaxy luminosity function (measured by local redshift surveys) and
find evidence of sampling problems. I compare the total luminosity
densities and find evidence of large scale structure influencing the
results.
M. J. Geller "
The Unexplored Redshift Survey" (2001, PASP, 113, 405)
L. N. da Costa "Galaxy
Redshift Surveys: 20 years later" (astro-ph/9812258)
L. N. da Costa "Galaxy
Redshift Surveys: 20 years later" (astro-ph/9812258)
M. J. Geller et al. "The
Century Survey: A Deeper Slice of the Universe" (1997, AJ, 114,
2205)
S. A. Shectman et al. "The
Las Campanas Redshift Survey" (1996, ApJ, 470, 172)
J. Loveday et
al. "The Stromlo-APM Redshift Survey. I - The luminosity function and space density of galaxies" (1992, ApJ, 390, 338)
V. de Lapparent, M. J. Geller and J. P. Huchra "A
slice of the universe" (1986, ApJ, 302, L1)
R. P. Kirshner et al. "A
million cubic megaparsec void in Bootes" (1981, ApJ, 248, L57)
The 2dF Galaxy Redshift Survey (2dFGRS) is a major new
spectroscopic survey carried out in the Anglo-Australian Observatory,
and integrated with the 2dF QSO survey. The survey aims to obtain
high-quality spectra and redshifts for 250,000 galaxies brighter than
~b_J=19.5. The galaxies cover an area of ~2000 sq.deg. selected from
both galactic caps.
The Sloan Digital Sky Survey (SDSS) is a very large
undertaking to map a quarter of the sky in 5 photometric bands (u',
g', r', i', and z') to about 23rd magnitude in g', r', and i', and to
take spectra of 10^6 galaxies and 10^5 QSOs. As opposed to 2dFGRS,
which can be considered to be its final state, SDSS will be running
for several more years.
D. G. York et al. "The
Sloan Digital Sky Survey: Technical Summary" (2000, AJ, 120,
1579)
Link to SDSS
publications
Link to 2dFGRS
publications
O. Le Fevre et al. "The VIRMOS-VLT Deep
Survey" (astro-ph/0101034)
B. Binggeli et al. "The luminosity function of galaxies" (1988, ARA\&A, 26, 509)
G. Efstathiou et al. "Analysis
of a complete galaxy redshift survey. II - The field-galaxy luminosity
function" (1988, MNRAS, 232, 431)
A. Sandage et al. "The
velocity field of bright nearby galaxies. I - The variation of mean
absolute magnitude with redshift for galaxies in a magnitude-limited
sample" (1979, ApJ, 232, 352)
W. J. Percival et al. "The 2dF Galaxy Redshift
Survey: The power spectrum and the matter content of the universe"
(astro-ph/0105252)
M. Tegmark et al. "Measuring
the Galaxy Power Spectrum with Future Redshift Surveys" (1998,
ApJ, 499, 555)
A. J. S. Hamilton et al. "Linear
redshift distortions and power in the IRAS Point Source Catalog
Redshift Survey" (2000, MNRAS, 317, L23)
A.J.S. Hamilton "Linear Redshift
Distortions: A Review" (astro-ph/9708102)
N. Kaiser "Clustering
in real space and in redshift space" (1987, MNRAS, 227, 1)
M. White and C. S. Kochanek "Completeness in
Photometric and Spectroscopic Searches for Clusters" (astro-ph/0110307)
J. Kepner et al. "An Automated Cluster Finder: The Adaptive Matched Filter" (1999, ApJ, 517, 78)
D. Zaritsky et al. "Distant Galaxy Clusters Identified from Optical Background Fluctuations" (1997, ApJ, 480, L91)
P. Coles "Large-Scale
Structure, Theory and Statistics" (astro-ph/0103017)
J. A. Peacocket al. "A
measurement of the cosmological mass density from clustering in the
2dF Galaxy Redshift Survey" (2001, Nature, 410, 169)
Y. Sigad et al. "Measuring
the Nonlinear Biasing Function from a Galaxy Redshift Survey"
(2000, ApJ, 540, 62)
R. H. Becker et al. "Evidence for
Reionization at z ~ 6: Detection of a Gunn-Peterson Trough in a z=6.28
Quasar" (astro-ph/0108097)
Z. Ivezic et al. "Solar System Objects
Observed in the SDSS Commissioning Data" (astro-ph/0105511)
Z. Haiman et al. "Constraints
on Cosmological Parameters from Future Galaxy Cluster Surveys"
(2001, ApJ, 553, 545)
D. J. Eisenstein et al. "Cosmic
Cosmic Complementarity: Joint Parameter Estimation from Cosmic
Microwave Background Experiments and Redshift Surveys" (1999, ApJ,
518, 2)
Schedule for Fall'2001:
"Organizational meeting" - Chris
Kochanek and Kris Stanek
0. September 12th, 2001Abstract:
How the course is organized. Motivation for the topic. Brief talk on
"How to give talks". Scheduling the talks.General reading material for the Semester:
P. J. E. Pebbles "Principles of Physical Cosmology"
"Redshift Surveys: How they are Done" - Warren R. Brown1. September 19th, 2001Abstract:
I will describe how to construct a redshift survey and summarize the
many technical issues involved. First, I describe what the terms
"redshift" and "redshift survey" mean. Selecting a redshift sample is
critically important to a survey. Performing accurate galaxy
photometry runs into issues of resolution, photometric calibration,
limiting surface brightness, k-corrections, and galactic extinction
corrections. Measuring galaxy velocities runs into the limitations of
spectrographs, errors in calibration and cross-correlation, and the
intrinsic motions of the galaxies themselves.Reading material:
W. R. Brown et al. "V-
and R- Galaxy Luminosity Functions and Low Surface Brightness Galaxies
in the Century Survey" (2001, AJ, 122, first six pages 714-719)
"Redshift Surveys: Why they are Done" - Alceste Bonanos2. September 26th, 2001Abstract:
Redshift surveys are very useful for measuring cosmological parameters
of the Universe and constraining models of it. We can learn a lot
about properties of galaxies by measuring the luminosity function and
finding its shape and normalization locally. Most importantly,
redshift surveys reveal the large scale structure of the
Universe. Statistical measures of galaxy clustering are the
correlation function and power spectrum. Describing mathematically the
clustering of galaxies with the above quantities, we can probe the
nature of dark matter, the form of primordial density fluctuations and
cosmological parameters (Omega and H_0). However, galaxy biasing is an
unresolved issue. Nonetheless, redshift surveys, together with the CMB
fluctuations, are the basis for understanding the nature and evolution
of structure in the Universe.Reading material:
M. J. Geller "
The Unexplored Redshift Survey" (2001, PASP, 113, 405)
"Redshift Surveys: How They Have Been Done" - Kenneth J. Rines3. October 3rd, 2001Abstract:
I will briefly describe some of the major redshift surveys of the past
25 years. Common themes in the history of redshift surveys are
improvements in sample size and selection and in our understanding of
selection effects. I will discuss some of the selection effects both
explicit and implicit in these surveys and show a few examples of how
different selection effects can yield dramatically different results.
Finally, I will discuss the advantages and disadvantages of different
types of redshift surveys for different applications. Reading material:
W. Saunders et al "The
PSCz catalogue" (2000, MNRAS, 317, 55)
"Redshift surveys past, present and future - part II" - Gaspar Bakos4. October 10th, 2001Abstract:
As a continuation of the previous talk in this series,
"Redshift surveys past, present and future", I will give technical
details on two recent major surveys, discuss similarities and
differences, and draft early results.Reading material:
M. Colless et al. "The 2dFGRS Galaxy
Redshift Survey: Spectra and redshifts" (astro-ph/0106498)
"Redshift surveys past, present and future - part III" - Craig Heinke5. October 17th, 2001Abstract:
I will discuss three redshift surveys that have not yet begun to take
spectra, but promise to take cosmology beyond Sloan. The
MMT/Hectospec combination will be very fast and effective in the range
0.1Reading material:
M. Davis and J. A. Newman "Mining the Sky with
Redshift Surveys" (astro-ph/0104418)
"Galaxy luminosity functions" - Mark A. Hartman6. October 24th, 2001 (in Classroom A)Abstract:
One of the fundamental measurements that can be made with the data
from a redshift survey is a determination of the galaxy luminosity
function. I will review the importance of this measurement and two
methods of determining the luminosity function: the parametric method
of Sandage, Tammann and Yahil, and the nonparametric stepwise
maximum-likelihood (SWML) method due to Efstathiou. The first
involves an overall fit of the data obtained to an assumed Schechter
function form of the luminosity function, while the second involves
binning the data to obtain an estimate of the luminosity function in
small steps of magnitude with no a priori assumption of its form.
Additionally, I discuss the implications of the measurement, current
values of the parameters involved, and the issues associated with
luminosity functions of galaxy samples with different morphologies and
other traits.Reading material:
H. Lin et al. "The
Luminosity Function of Galaxies in the Las Campanas Redshift
Survey" (1996, ApJ, 464, 60)
"Galaxy power spectrum" - Scott Schnee7. October 31st, 2001Abstract:
Although the overall properties of the universe are close to being
homogeneous, redshift surveys have revealed structures exceeding the
size of 100 Mpc. The existence of these structures tells us about the
initial conditions of the big bang and the cosmological parameters
that describe the universe. One way to quantify the amount and scale
of the inhomogeneities is the power spectrum. I will discuss the
basic theory behind the power spectrum, the complexities in actually
measuring it, and some recent results.
Reading material:
B. A. Allgood et al. "The Three-Dimensional Power Spectrum Measured from 2MASS" (astro-ph/0109403)
"Redshift space distortions" - Steven Furlanetto8. November 7th, 2001Abstract:
The mapping between our distance measurements (via redshifts) and the
true distance is not perfect because each galaxy has its own peculiar
velocity. However, this imperfect transformation can be turned to our
advantage because the peculiar velocities are primarily caused by
large-scale coherent infall into matter overdensities. I will review
the theory of linear redshift space distortions and explain how they
allow one to measure a particular function of the bias parameter of
galaxies and the cosmological parameters. I will also review recent
measurements of redshift space distortions, focusing on those from the
IRAS PSCz and 2dF redshift surveys.Reading material:
J. A. Peacock et al. "A measurement of the
cosmological mass density from clustering in the 2dF Galaxy Redshift
Survey" (2001, Nature, 410, 169)
"Finding clusters and superclusters of galaxies" - Daniel Marrone9. November 14th, 2001Abstract:
Galaxy clusters are powerful cosmological tools. They can be used to
examine large scale structure and to determine the amount of dark
matter on Mpc scales. Their abundance and redshift distribution can be
used to determine cosmological parameters and constrain the nature of
dark energy. These applications require large catalogues of galaxy
clusters with well understood biases and selection effects and this
has led to the development of a variety of methods of cluster
identification. I will examine the prominent cluster identification
methods and discuss their application to surveys with spectroscopic
redshifts, photometric redshifts, or no redshift information at all. I
will also summarize the performance of each method when applied to
real and/or simulated data.Reading material:
R. Kim et al. "Detecting Clusters
of Galaxies in the Sloan Digital Sky Survey I : Monte Carlo Comparison
of Cluster Detection Algorithms" (astro-ph/0110259)
"Galaxy biasing" - Brant
E. Robertson 10. November 21st, 2001Abstract:
Determining the relation between the observed galaxy distribution and
the underlying mass distribution remains an unsolved problem.
Redshift surveys can contribute to a solution of this problem through
observational measures of the galaxy-galaxy correlation function and
redshift space distortions. In this discussion I review the concept
of galaxy bias, considering both linear and nonlinear bias. I will
discuss theoretically and observationally oriented treatments of bias
and the effectiveness of observations from current redshift surveys to
measure galaxy bias.Reading material:
Brant's talk
"Serendipitous science from redshift surveys" - Maryam Modjaz11. November 28th, 2001Abstract:
Extensive redshift surveys inevitably capture astronomical objects
besides their targets of interest. I will review three instances in
which the Sloan Digital Sky Survey (SDSS) has yielded serendipitous
science, spanning a wide range of redshifts: Solar System objects,
Galactic halo objects and high-redshift quasars. For each, I will
describe the methods used to obtain and select data and indicate the
tests performed. I will present the importance of the findings while
emphasizing the special features of SDSS that made these findings
possible.Reading material:
H. J. Newberg et al. "The Ghost of Sagittarius
and Lumps in the Halo of the Milky Way" (astro-ph/0111095)
"Joint parameter estimation from Redshift Surveys, SNe and CMB
experiments" - Alexia E. Schulz
12. December 5th, 2001Abstract:
Many recent studies suggest that redshift surveys may become a
valuable tool for studying the cosmological parameters. Particular
attention has been given to the question of whether or not redshift
surveys could help cosmologists probe the nature of the dark energy
now believed to dominate the energy density in the universe. I will
begin with a thorough discussion of the statistical tools often used
in these analyses, and discuss how to combine the results of different
experiments to strengthen the constraints. I will briefly survey the
predictions for the constraints from several upcoming cosmological
observations, focusing on the dark energy results. I will conclude by
discussing strategies for designing redshift surveys that will
optimize the constraints when the results are combined with other
experiments.Reading material:
T. Matsubara, A. S. Szalay "Constraining the Cosmological Constant from Large-Scale Redshift-Space Clustering" (2001, ApJ, 556, L67)
"Hubble Deep Fields" - Paul T. Kondratko
13. December 12th, 2001Abstract:
Reading material:
Questions or Comments?
Send an e-mail to kstanek@cfa.harvard.edu.
This page was last updated on December 4th, 2001.