Johnston AST-0607852 Guhathakurta AST-0607726 Majewski AST-0607377 Bullock
This collaborative project across four institutions has at its heart the first large-scale spectroscopic survey of the halo of M31, the Andromeda Galaxy. Imaging surveys appear to have discovered large streamers as well as an overall smooth population, and this study aims to understand the nature and origin of this halo and its structure. The combination of observational facilities and techniques to be used should be much more efficient than prior studies, and the anticipated sample will contain thirty times as many radial velocity measurements as previously made in the halo of M31. This study not only will derive a mean metallicity distribution function, outer rotation curve, and velocity dispersion for the M31 halo, but more importantly it will assess the extent to which the disruption of satellite galaxies has contributed to the halo population. The expected discrete streams of material in radial velocity and abundance will provide a visual record of the accretion history of the M31 halo.
Women and other under-represented groups will participate at the undergraduate and research level at all four of the collaborating institutions. Each member of the research team gives regular public lectures and presentations in K-12 classrooms. As our nearest large spiral galaxy, M31 is well known to the public, so it is likely that research results can be made readily accessible to non-scientists.