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Title: Axion dark matter: strings and their cores

Abstract

Axions constitute a well-motivated dark matter candidate, and if PQ symmetry breaking occurred after inflation, it should be possible to make a clean prediction for the relation between the axion mass and the axion dark matter density. We show that axion (or other global) string networks in 3D have a network density that depends logarithmically on the string separation-to-core ratio. This logarithm would be about 10 times larger in axion cosmology than what we can achieve in numerical simulations. We simulate axion production in the early Universe, finding that, for the separation-to-core ratios we can achieve, the changing density of the network has little impact on the axion production efficiency.

Authors:
 [1];  [2]
  1. McGill University, Department of Physics, 3600 rue University, Montréal QC H3A 2T8 (Canada)
  2. Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 2, D-64289 Darmstadt (Germany)
Publication Date:
OSTI Identifier:
22525091
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 01; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AXIONS; COMPUTERIZED SIMULATION; COSMOLOGICAL INFLATION; COSMOLOGY; DENSITY; EFFICIENCY; INFLATIONARY UNIVERSE; MASS; NONLUMINOUS MATTER; SYMMETRY BREAKING; UNIVERSE

Citation Formats

Fleury, Leesa, and Moore, Guy D., E-mail: fleuryle@physics.mcgill.ca, E-mail: guy.moore@physik.tu-darmstadt.de. Axion dark matter: strings and their cores. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/01/004.
Fleury, Leesa, & Moore, Guy D., E-mail: fleuryle@physics.mcgill.ca, E-mail: guy.moore@physik.tu-darmstadt.de. Axion dark matter: strings and their cores. United States. doi:10.1088/1475-7516/2016/01/004.
Fleury, Leesa, and Moore, Guy D., E-mail: fleuryle@physics.mcgill.ca, E-mail: guy.moore@physik.tu-darmstadt.de. 2016. "Axion dark matter: strings and their cores". United States. doi:10.1088/1475-7516/2016/01/004.
@article{osti_22525091,
title = {Axion dark matter: strings and their cores},
author = {Fleury, Leesa and Moore, Guy D., E-mail: fleuryle@physics.mcgill.ca, E-mail: guy.moore@physik.tu-darmstadt.de},
abstractNote = {Axions constitute a well-motivated dark matter candidate, and if PQ symmetry breaking occurred after inflation, it should be possible to make a clean prediction for the relation between the axion mass and the axion dark matter density. We show that axion (or other global) string networks in 3D have a network density that depends logarithmically on the string separation-to-core ratio. This logarithm would be about 10 times larger in axion cosmology than what we can achieve in numerical simulations. We simulate axion production in the early Universe, finding that, for the separation-to-core ratios we can achieve, the changing density of the network has little impact on the axion production efficiency.},
doi = {10.1088/1475-7516/2016/01/004},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 01,
volume = 2016,
place = {United States},
year = 2016,
month = 1
}
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