Sufficiency of SIDM core-collapse accretion to explain Sgr A* mass growth

Determine whether the increase in central dark-matter density during self-interacting dark matter (SIDM) halo core collapse in the Milky Way can drive an accretion rate onto Sgr A* sufficient to reproduce the observed supermassive black hole mass growth of order 0.06 × 10^6 solar masses per year.

Background

The paper compiles three decades of Sgr A* mass measurements and fits models that strongly favor a linear increase in the supermassive black hole mass. Gas accretion at the required rate is argued to be implausible due to severe Eddington-limit violations, and standard cold dark matter accretion is considered too small over a Hubble time.

As an alternative, the authors suggest that a core collapse of a self-interacting dark matter (SIDM) halo could dramatically raise central dark-matter densities and thereby enhance dark-matter accretion. They explicitly state that it remains to be determined whether this mechanism can quantitatively account for the measured growth rate.