Superfluid Dark Matter around Black Holes

Abstract

Superfluid dark matter, consisting of self-interacting light particles that thermalize and condense to form a superfluid in galaxies, provides a novel theory that matches the success of the standard $\Lambda$CDM model on cosmological scales while simultaneously offering a rich phenomenology on galactic scales. Within galaxies, the dark matter density profile consists of a nearly homogeneous superfluid core surrounded by an isothermal envelope. In this work we compute the density profile of superfluid dark matter around supermassive black holes at the center of galaxies. We show that, depending on the fluid equation of state, the dark matter profile presents distinct power-law behaviors, which can be used to distinguish it from the standard results for collisionless dark matter.