A new mass model for M31 is presented. The best possible baryonic mass profile for M31 is derived from the 2MASS Ks-band image and M/L ratios from Bell et al. (2003). The best fitting rotation curve is then found within the context of CDM disk galaxy formation. We find that M31 is well-described by a model that includes an adiabatically contracted halo, with an initial NFW concentration, c = 20. Models without adiabatic contraction fail to reproduce the observed rotation curve at r>15 kpc. The derived halo virial mass is Mvir = (9.4 0.8) 1011M, consistent with masses derived from other observational methods.
|Original language||English (US)|
|Number of pages||1|
|Journal||Proceedings of the International Astronomical Union|
|State||Published - Aug 2006|