A semi-analytic dynamical friction model for cored galaxies

Understand

We present a dynamical friction model based on Chandrasekhar's formula that reproduces the fast inspiral and stalling experienced by satellites orbiting galaxies with a large constant density core.

• We show that the fast inspiral phase does not owe to resonance.
• Rather, it owes to the background velocity distribution function for the constant density cores being dissimilar from the usually-assumed Maxwellian distribution.
• Using the correct background velocity distribution function and the semi-analytic model from Petts et al.