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Title: Condensation of galactic cold dark matter

Abstract

We consider the steady-state regime describing the density profile of a dark matter halo, if dark matter is treated as a Bose-Einstein condensate. We first solve the fluid equation for “canonical” cold dark matter, obtaining a class of density profiles which includes the Navarro-Frenk-White profile, and which diverge at the halo core. We then solve numerically the equation obtained when an additional “quantum pressure” term is included in the computation of the density profile. The solution to this latter case is finite at the halo core, possibly avoiding the “cuspy halo problem” present in some cold dark matter theories. Within the model proposed, we predict the mass of the cold dark matter particle to be of the order of M{sub χ}c{sup 2}≈10{sup −24} eV, which is of the same order of magnitude as that predicted in ultra-light scalar cold dark matter models. Finally, we derive the differential equation describing perturbations in the density and the pressure of the dark matter fluid.

Authors:
 [1]
  1. Nordita, KTH Royal Institute of Technology and Stockholm University,SE-106 91 Stockholm (Sweden)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22572113
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 07; Other Information: PUBLISHER-ID: JCAP07(2016)009; OAI: oai:repo.scoap3.org:16318; cc-by Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOSE-EINSTEIN CONDENSATION; CALCULATION METHODS; COSMOLOGY; DIFFERENTIAL EQUATIONS; FIELD EQUATIONS; GRAVITATION; MATHEMATICAL SOLUTIONS; NONLUMINOUS MATTER; PERTURBATION THEORY

Citation Formats

Visinelli, Luca. Condensation of galactic cold dark matter. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/07/009.
Visinelli, Luca. Condensation of galactic cold dark matter. United States. doi:10.1088/1475-7516/2016/07/009.
Visinelli, Luca. 2016. "Condensation of galactic cold dark matter". United States. doi:10.1088/1475-7516/2016/07/009.
@article{osti_22572113,
title = {Condensation of galactic cold dark matter},
author = {Visinelli, Luca},
abstractNote = {We consider the steady-state regime describing the density profile of a dark matter halo, if dark matter is treated as a Bose-Einstein condensate. We first solve the fluid equation for “canonical” cold dark matter, obtaining a class of density profiles which includes the Navarro-Frenk-White profile, and which diverge at the halo core. We then solve numerically the equation obtained when an additional “quantum pressure” term is included in the computation of the density profile. The solution to this latter case is finite at the halo core, possibly avoiding the “cuspy halo problem” present in some cold dark matter theories. Within the model proposed, we predict the mass of the cold dark matter particle to be of the order of M{sub χ}c{sup 2}≈10{sup −24} eV, which is of the same order of magnitude as that predicted in ultra-light scalar cold dark matter models. Finally, we derive the differential equation describing perturbations in the density and the pressure of the dark matter fluid.},
doi = {10.1088/1475-7516/2016/07/009},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 07,
volume = 2016,
place = {United States},
year = 2016,
month = 7
}
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