The local dark matter phase-space density and impact on WIMP direct detection

Abstract

We present a new determination of the local dark matter phase-space density. This result is obtained implementing, in the limit of isotropic velocity distribution and spherical symmetry, Eddington's inversion formula, which links univocally the dark matter distribution function to the density profile, and applying, within a Bayesian framework, a Markov Chain Monte Carlo algorithm to sample mass models for the Milky Way against a broad and variegated sample of dynamical constraints. We consider three possible choices for the dark matter density profile, namely the Einasto, NFW and Burkert profiles, finding that the velocity dispersion, which characterizes the width in the distribution, tends to be larger for the Burkert case, while the escape velocity depends very weakly on the profile, with the mean value we obtain being in very good agreement with estimates from stellar kinematics. The derived dark matter phase-space densities differ significantly--most dramatically in the high velocity tails--from the model usually taken as a reference in dark matter detection studies, a Maxwell-Boltzmann distribution with velocity dispersion fixed in terms of the local circular velocity and with a sharp truncation at a given value of the escape velocity. We discuss the impact of astrophysical uncertainties on dark matter scattering rates and direct detection exclusion limits, considering a few sample cases and showing that the most sensitive ones are those for light dark matter particles and for particles scattering inelastically. As a general trend, when adopting a self-consistent phase-space density, we find that rates are larger, and hence exclusion limits stronger, than with the standard Maxwell-Boltzmann approximation. Tools for applying our result on the local dark matter phase-space density to other dark matter candidates or experimental setups are provided.

24 pages, 11 figures. Revised to match version accepted in JCAP. References updated

References in corpus (11)

• First results from DAMA/LIBRA and the combined results with DAMA/NaI
• Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector
• Results from 730 kg days of the CRESST-II Dark Matter Search
• The Milky Way's Circular Velocity Curve to 60 kpc and an Estimate of the Dark Matter Halo Mass from Kinematics of ~2400 SDSS Blue Horizontal Branch Stars
• The RAVE Survey: Constraining the Local Galactic Escape Speed
• Phase-space structure in the local dark matter distribution and its signature in direct detection experiments
• Annual Modulation of Dark Matter in the Presence of Streams
• The Dark Matter at the End of the Galaxy
• Low-threshold analysis of CDMS shallow-site data
• Compatibility of DAMA/LIBRA dark matter detection with other searches in light of new Galactic rotation velocity measurements
• Ultra-fine dark matter structure in the Solar neighbourhood

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