Cored density profiles in the DARKexp model

Abstract

The DARKexp model represents a novel and promising attempt to solve a long standing problem of statistical mechanics, that of explaining from first principles the quasi--stationary states at the end of the collisionless gravitational collapse. The model, which yields good fits to observation and simulation data on several scales, was originally conceived to provide a theoretical basis for the $1/r$ cusp of the Navarro--Frenk--White profile. In this note we show that it also allows for cored density profiles that, when viewed in three dimensions, in the $r\to0$ limit have the conical shape characteristic of the Burkert profile. It remains to be established whether both cusps and cores, or only one of the two types, are allowed beyond the asymptotic analysis of this work.