0 Assigned ID: 1061 ----- Attempting Submission 1 (Fri Apr 11 23:35:11 GMT 2014) ----- HST Phase I Proposal 1061 (aptform.apt) successfully submitted. ----- Attempting Submission 2 (Fri Apr 11 23:57:00 GMT 2014) ----- We propose to conduct N-body and hydrodynamic simulations of the impact of M31's Giant Southern Stream (GSS) progenitor on M31's disk. The GSS is believed to represent a merger of a LMC-sized galaxy within the last Gyr, and the orbital parameters of the merger have been well constrained by a combination of positional, kinematic, and distance measurements. Because of the wealth of HST and ground-based data on M31's disk, the M31-GSS system represents one of the best laboratories for understanding the effect of minor mergers on the disk morphology and star formation properties of spiral galaxies. We will adopt a range of progenitor stellar and total masses, orbital parameters, and M31 virial masses, as provided by a recent Bayesian study of this system. Using N-body runs, we will focus on the tidal tails, warping, disk heating, and other dynamical features of M31's disk. Then using full hydrodynamic runs, we will focus on the spatially resolved star formation history in M31's disk. We will make our simulations publicly available for comparison with observational surveys such as the large PHAT survey of M31's disk. UNRESOLVED STELLAR POPULATIONS AND GALAXY STRUCTURE Default Small false false false false true SUPPORTED