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arXiv · hep-ph/9303313

Axion Miniclusters and Bose Stars

Edward W. Kolb·Igor I. Tkachev
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Abstract

Evolution of inhomogeneities in the axion field around the QCD epoch is studied numerically, including for the first time important non-linear effects. It is found that perturbations on scales corresponding to causally disconnected regions at $T \sim 1 \, {\rm GeV}$ can lead to very dense axion clumps, with present density $ρ_a \ga 10^{-8}\,{\rm g \, cm^{-3}}$. This is high enough for the collisional $2a \rightarrow 2a$ process to lead to Bose--Einstein relaxation in the gravitationally bound clumps of axions, forming Bose stars.

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Edward W. Kolb, Igor I. Tkachev. 1993-03-29. Axion Miniclusters and Bose Stars. https://doi.org/10.1103/physrevlett.71.3051

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