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arXiv · 1310.1774

Axions as Hot and Cold Dark Matter

Kwang Sik Jeong·Masahiro Kawasaki·Fuminobu Takahashi
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Abstract

The presence of a hot dark matter component has been hinted at 3 sigma by a combination of the results from different cosmological observations. We examine a possibility that pseudo Nambu-Goldstone bosons account for both hot and cold dark matter components. We show that the QCD axions can do the job for the axion decay constant f_a < O(10^10) GeV, if they are produced by the saxion decay and the domain wall annihilation. We also investigate the cases of thermal QCD axions, pseudo Nambu-Goldstone bosons coupled to the standard model sector through the Higgs portal, and axions produced by modulus decay.

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Kwang Sik Jeong, Masahiro Kawasaki, Fuminobu Takahashi. 2013-10-07. Axions as Hot and Cold Dark Matter. https://doi.org/10.1088/1475-7516%2F2014%2F02%2F046

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