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arXiv · 1004.2682

Axion Bose-Einstein Condensation: a model beyond Cold Dark Matter

Q. Yang
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Abstract

Cold dark matter axions form a Bose-Einstein condensate if the axions thermalize. Recently, it was found that they do thermalize when the photon temperature reaches T ~ 100 eV(f/10^12GeV)^1/2 and that they continue to do so thereafter. We discuss the differences between axion BEC and CDM in the linear regime and the non-linear regime of evolution of density perturbations. We find that axion BEC provides a mechanism for the production of net overall rotation in dark matter halos, and for the alignment of cosmic microwave anisotropy multi-poles.

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Q. Yang. 2010-04-15. Axion Bose-Einstein Condensation: a model beyond Cold Dark Matter. https://doi.org/10.1063/1.3489564

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