Are the Ogle Microlenses in the Galactic Bar?

Details Are the Ogle Microlenses in the Galactic Bar? Are the Ogle Microlenses in the Galactic Bar?

1994-07-04

arxiv.org/abs/astro-ph/9407010v3

Astrophys.J.435:L113-L116,1994

Astronomy and Astrophysics

Astrophysics

10 pages, 2 figures, revised version accepted for the publication in ApJL, uses AAS LaTeX aaspp.sty macro, PostScript figures

Scientific paper

10.1086/187607

The analysis of the first two years of OGLE data revealed 9 microlensing events of the galactic bulge stars, with the characteristic time scales in the range $ 8.6 < t_0 < 62 $ days, where $ t_0 = R_E / V $. The optical depth to microlensing is larger than $ ( 3.3 \pm 1.2 ) \times 10^{-6}$, in excess of current theoretical estimates, indicating a much higher efficiency for microlensing by either bulge or disk lenses. We argue that the lenses are likely to be ordinary stars in the galactic bar, which has its long axis elongated towards us. A relation between $ t_0 $ and the lens masses remains unknown until a quantitative model of bar microlensing becomes available. At this time we have no evidence that the OGLE events are related to dark matter. The geometry of lens distribution can be determined observationally when the microlensing rate is measured over a larger range of galactic longitudes, like $ -10^o < l < +10^o $, and the relative proper motions of the galactic bulge (bar) stars are measured with the HST.

Affiliated with

Also associated with

No associations

Rating

Are the Ogle Microlenses in the Galactic Bar? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Are the Ogle Microlenses in the Galactic Bar?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Are the Ogle Microlenses in the Galactic Bar? will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-580630