The shapes of dark matter dominated dwarf spheroidal stellar density profiles

Abstract

A Bayesian likelihood analysis of the stellar density profile shapes of several dark matter dominated Galactic dwarf spheroidal galaxies (dSphs) has been completed. This analysis indicates that the inner power law, ρ\propto r^{-γ}, of each of these profiles satisfies γ< 1.21 at greater than 99% confidence with a slight preference for γ\sim 0.7 . Speculating that this bound on the stellar profiles may be related to the inner power law of the underlying dark matter distribution reveals a statistical discrepancy with the values favoured by recent N-body simulations of cold dark matter (CDM), γ_{CDM} \sim 1.4-1.5 .