Dark Matter distribution in the Milky Way: microlensing and dynamical constraints

TL;DR

This paper uses microlensing and dynamical data to constrain the local Dark Matter density and profile in the Milky Way, supporting standard profiles and ruling out extreme compressed models.

Contribution

It provides new constraints on the Dark Matter distribution in the Milky Way using combined microlensing and dynamical observations with advanced baryonic models.

Findings

Standard Dark Matter profiles are consistent with observations.

Extreme adiabatically compressed profiles are ruled out.

Estimated local Dark Matter density is 0.20-0.56 GeV/cm^3.

Abstract

We show that current microlensing and dynamical observations of the Galaxy permit to set interesting constraints on the Dark Matter local density and profile slope towards the galactic centre. Assuming state-of-the-art models for the distribution of baryons in the Galaxy, we find that the most commonly discussed Dark Matter profiles (viz. Navarro-Frenk-White and Einasto) are consistent with microlensing and dynamical observations, while extreme adiabatically compressed profiles are robustly ruled out. When a baryonic model that also includes a description of the gas is adopted, our analysis provides a determination of the local Dark Matter density, \rho_0=0.20-0.56 GeV/cm^3 at 1\sigma, that is found to be compatible with estimates in the literature based on different techniques.