A new model for dark matter phase space distribution

Zhen Li, Steen H. Hansen

Published 2023-12-19Version 1

Understanding the nature of dark matter is among the top priorities of modern physics. However, due to its inertness, it is very difficult to detect and study it directly in terrestrial experiments. Numerical N-body simulations are currently the best approach to study the particle properties and phase space distribution, by assuming the collisionless nature of dark matter particles. These simulations also compensate for the fact that we do not have a satisfactory theory for predicting the universal properties of dark matter halos, such as the density profile and velocity distribution. In this work, we propose a new analytical model of dark matter phase space distribution that could provide a NFW-like density profile and velocity distribution, as well as velocity component distributions, which agree very well with the simulation data. Our model is relevant both for theoretical modelling of dark matter distributions, as well as for underground detector experiments, which need the dark matter velocity distribution for the experimental analysis.