Re-interpretation of "Bar slowdown and the distribution of dark matter in barred galaxies" by Athanassoula

Abstract

Athanassoula (2014) has claimed that measurements of the ratio of corotation radius to bar length in galaxies do not place a constraint on the disk to halo mass ratio. Her conclusion was based on a series of simulations published by Athanassoula et al. (2013). Here we show that these results are, in fact, consistent with previous work on the slow down of bars due to dynamical friction because gas inflow rearranges the disk mass before the bar settles. It therefore remains true that a bar rotating sufficiently fast that corotation is not far beyond the bar end requires a near maximum disk.