A New Luminosity Function for the Galactic Bulge

Abstract:

We present a new calculation of the luminosity function of stars in the Galactic bulge. We describe our analysis of archival HST data combined with VISTA VIRCAM-VVV survey data and Microlensing Observations in Astrophysics (MOA) data and include in-depth discussions of calibration, charge transfer efficiency, CR removal, and disk star decontamination. We describe how the luminosity function, thus mass function, varies with Galactic latitude and how this calculation permits a new estimate of the exoplanet microlensing event rate in portions of the Galactic bulge not accessible to current survey methods due to obscuration by dust. Finally, we outline the general characteristics of the observed populations and discuss implications for field selection for NASA's Wide-Field Infrared Survey Telescope mission.