The Galactic bulge as seen in optical surveys

TL;DR

This paper investigates the Galactic bulge using optical surveys, modeling stellar density and extinction to assess Gaia's capability to observe bulge stars, complemented by ongoing observational analysis.

Contribution

It combines the Besancon Galaxy model and 3D extinction maps to evaluate the observability of bulge stars with Gaia and presents initial observational results.

Findings

Estimated stellar density variations across the bulge

Assessed Gaia's potential to measure bulge stars despite crowding and extinction

Presented preliminary analysis from CFHT observations

Abstract

The bulge is a region of the Galaxy of tremendous interest for understanding galaxy formation. However measuring photometry and kinematics in it raises several inherent issues, such as severe crowding and high extinction in the visible. Using the Besancon Galaxy model and a 3D extinction map, we estimate the stellar density as a function of longitude, latitude and apparent magnitude and we deduce the possibility of reaching and measuring bulge stars with Gaia. We also present an ongoing analysis of the bulge using the Canada-France-Hawaii Telescope.