Far out: tracing the mass in M31

Recent photometric surveys have shown that the disk and halo of M31, the Andromeda galaxy, extend much further than previously thought, and contain stellar streams and arcs which indicate the complex history of this galaxy. We propose to examine the outer disk and halo of M31 from an infrared perspective. By extending the existing IRAC maps of the galaxy, we can trace the stellar mass to larger radii, better constraining mass models. An improved understading of the stellar populations in these remote areas will provide more detailed clues about the interaction history of the galaxy.