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Title: Derivation of the anisotropy profile, constraints on the local velocity dispersion, and implications for direct detection

Abstract

We study the implications of a pseudo-phase-space density power-law for the anisotropy profile of a Milky Way-like dark matter halo. Requiring that the anisotropy parameter does not take non-physical values within the virial radius places a maximum value on the local radial velocity dispersion. For a plausible range of halo parameters, it is possible to take a local total velocity dispersion of up to about 300 km/s. Making this choice uniquely specifies the anisotropy and dispersion profiles. We introduce a way to model the local velocity distribution that incorporates this anisotropy and study the impact on direct detection.

Authors:
 [1]
  1. Physics Department and The McDonnell Center for the Space Sciences, Washington University, St. Louis, MO, 63130 (United States)
Publication Date:
OSTI Identifier:
22369761
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 02; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; DISTRIBUTION; LIMITING VALUES; MILKY WAY; NONLUMINOUS MATTER; POWER DENSITY; RADIAL VELOCITY

Citation Formats

Hunter, Daniel R., E-mail: dhunter@physics.wustl.edu. Derivation of the anisotropy profile, constraints on the local velocity dispersion, and implications for direct detection. United States: N. p., 2014. Web. doi:10.1088/1475-7516/2014/02/023.
Hunter, Daniel R., E-mail: dhunter@physics.wustl.edu. Derivation of the anisotropy profile, constraints on the local velocity dispersion, and implications for direct detection. United States. doi:10.1088/1475-7516/2014/02/023.
Hunter, Daniel R., E-mail: dhunter@physics.wustl.edu. 2014. "Derivation of the anisotropy profile, constraints on the local velocity dispersion, and implications for direct detection". United States. doi:10.1088/1475-7516/2014/02/023.
@article{osti_22369761,
title = {Derivation of the anisotropy profile, constraints on the local velocity dispersion, and implications for direct detection},
author = {Hunter, Daniel R., E-mail: dhunter@physics.wustl.edu},
abstractNote = {We study the implications of a pseudo-phase-space density power-law for the anisotropy profile of a Milky Way-like dark matter halo. Requiring that the anisotropy parameter does not take non-physical values within the virial radius places a maximum value on the local radial velocity dispersion. For a plausible range of halo parameters, it is possible to take a local total velocity dispersion of up to about 300 km/s. Making this choice uniquely specifies the anisotropy and dispersion profiles. We introduce a way to model the local velocity distribution that incorporates this anisotropy and study the impact on direct detection.},
doi = {10.1088/1475-7516/2014/02/023},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 02,
volume = 2014,
place = {United States},
year = 2014,
month = 2
}
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