1995/08/01 by K. Z. Stanek, Mario Mateo, Stanek, K. Z. +15
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9508008
4 pages, uuencoded compressed PostScript, talk presented at the IAU Colloquium 157 "Barred Galaxies"; also available through WWW at http://www.astro.princeton.edu/~library/prep.html
arxiv created 1995/08/01 · openalex publication_date 1995/08/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The color-magnitude diagrams of ∼ 1 × 106 stars obtained for 19 fields towards the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump stars. We found that the distributions of the extinction-adjusted apparent magnitudes of red clump stars in fields lying at l=±5° in galactic longitude differ by ∼ 0.4 mag. A plausible explanation of this observed difference in the luminosity distribution is that the Galactic bulge is a triaxial structure, or a bar, which is inclined to the line of sight by no more than 45°. The part of the bar at the positive galactic longitude is closer to us. Work is now under way to model the Galactic bar by fitting the observed luminosity functions in the red clump region for various fields. Preliminary results indicate that the angle of the inclination of the bar to the line of sight can be as small as ∼20°. Gravitational microlensing can provide us with additional constrains on the structure of the Galactic bar.