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Title: Dark matter halos with cores from hierarchical structure formation

Abstract

We show that dark matter emerging from late decays (z < or approx.1000) produces a linear power spectrum identical to that of cold dark matter (CDM) on all observationally relevant scales (> or approx. 0.1 Mpc), and simultaneously generates observable constant-density cores in small dark matter halos. We refer to this class of models as meta-cold dark matter (mCDM), because it is born with nonrelativistic velocities from the decays of cold thermal relics. The constant-density cores are a result of the low phase-space density of mCDM at birth. Warm dark matter cannot produce similar size phase-space limited cores without saturating the Ly{alpha} power spectrum bounds. Dark matter-dominated galaxy rotation curves and stellar velocity dispersion profiles may provide the best means to discriminate between mCDM and CDM. mCDM candidates are motivated by the particle spectrum of supersymmetric and extra dimensional extensions to the standard model of particle physics.

Authors:
; ;  [1]
  1. Center for Cosmology, Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)
Publication Date:
OSTI Identifier:
21020115
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.061303; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COSMOLOGY; DENSITY; ENERGY SPECTRA; GALAXIES; NONLUMINOUS MATTER; PHASE SPACE; ROTATION; STANDARD MODEL; SUPERSYMMETRY; VELOCITY

Citation Formats

Strigari, Louis E., Kaplinghat, Manoj, and Bullock, James S. Dark matter halos with cores from hierarchical structure formation. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.061303.
Strigari, Louis E., Kaplinghat, Manoj, & Bullock, James S. Dark matter halos with cores from hierarchical structure formation. United States. doi:10.1103/PHYSREVD.75.061303.
Strigari, Louis E., Kaplinghat, Manoj, and Bullock, James S. Thu . "Dark matter halos with cores from hierarchical structure formation". United States. doi:10.1103/PHYSREVD.75.061303.
@article{osti_21020115,
title = {Dark matter halos with cores from hierarchical structure formation},
author = {Strigari, Louis E. and Kaplinghat, Manoj and Bullock, James S.},
abstractNote = {We show that dark matter emerging from late decays (z < or approx.1000) produces a linear power spectrum identical to that of cold dark matter (CDM) on all observationally relevant scales (> or approx. 0.1 Mpc), and simultaneously generates observable constant-density cores in small dark matter halos. We refer to this class of models as meta-cold dark matter (mCDM), because it is born with nonrelativistic velocities from the decays of cold thermal relics. The constant-density cores are a result of the low phase-space density of mCDM at birth. Warm dark matter cannot produce similar size phase-space limited cores without saturating the Ly{alpha} power spectrum bounds. Dark matter-dominated galaxy rotation curves and stellar velocity dispersion profiles may provide the best means to discriminate between mCDM and CDM. mCDM candidates are motivated by the particle spectrum of supersymmetric and extra dimensional extensions to the standard model of particle physics.},
doi = {10.1103/PHYSREVD.75.061303},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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