The Color‐Magnitude Diagram in Baade's Window Revisited

Abstract
We have reanalyzed the OGLE $V$ and $I$ photometry of $sim 500,000$ stars in Baade's Window, and we confirm the extinction map published by Stanek (1996). However, we find that the interpretation of the OGLE color--magnitude diagram for the disk stars proposed by Paczy'nski et al. (1994) was incorrect: the dominant disk population in Baade's Window is old, and we find no evidence for a large hole in the inner Galactic disk. We find evidence for a small systematic error in the OGLE photometry for stars below the ``red clump'': the faint stars with $V>18$ have their $(V-I)$ color indices too red by $sim 0.1;mag$. We find tentative evidence from the OGLE and HST photometry that the the bulge main sequence turn--off point is brighter by $sim 0.5 ;mag$ than it is in either 47~Tuc or NGC~6791, indicating that the dominant population of the Galactic bulge is considerably younger than those clusters.Comment: submitted to the Astrophysical Journal, 17 pages, 9 figures, 4 figures included; all figures are available using ftp://www.astro.princeton.edu/stanek/Kirag
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