Stellar Microscopy

Gravitational microlensing can be used for imaging the surfaces of distant stars.

Papers:

The Chromaticity of Microlensing, Sasselov, D.D., 1997, in Variable Stars and the Astrophysical Returns of Microlensing Surveys, eds. R. Ferlet and J.P. Maillard, Editions Frontieres - Paris, p.141 (astro-ph/9702180).

Surface Imaging by Microlensing, Sasselov, D.D., 1998, in Cool Stars, Stellar Systems, and the Sun, 10th Cambridge Workshop, eds. R. Donahue and J. Bookbinder, ASP Conf. Ser. 154, 383-391 (astro-ph/9801229 ).

Probing Red Giant Atmospheres with Gravitational Microlensing, D. Heyrovsky, D. Sasselov, A. Loeb, 2000, ApJ, in press (astro-ph/9902273).

Detecting Stellar Spots by Gravitational Microlensing, D. Heyrovsky, & D. Sasselov, 2000, ApJ, 529, 69.

NEW ALERTS from OGLE-III.

Other surveys: MACHO, EROS, or PLANET:

EROS 2000-BLG-5 .
See also the EROS Web page, for a finding chart and light curves.

OBSERVING INSTRUCTIONS:

Ideally obtain 2 spectra (near H-alpha) of 20 minutes each on the night of the event peak ("caustic crossing"). The exact time for EROS 2000-BLG-5 will be announced on the "latest updates" Web page above. Currently (06/30/2000) the peak is expected to occur on any of the July 1-4th nights. No special requirements on the spectral resolution - S/N should be maximized. The amplified star will likely not exceed V=15 mag.

Target-of-Opportunity Program (D. Sasselov & D. Heyrovsky) on FLWO 60-inch -
text (PostScript) of the 1998 proposal.
Proposal front page.