Axion miniclusters and Bose stars.

  title={Axion miniclusters and Bose stars.},
  author={Kolb and Tkachev},
  journal={Physical review letters},
  volume={71 19},
  • Kolb, Tkachev
  • Published 29 March 1993
  • Physics, Materials Science
  • Physical review letters
Evolution of inhomogeneities in the axion field around the QCD epoch is studied numerically, including for the first time important nonlinear effects. It is found that perturbations on scales corresponding to causally disconnected regions at T\ensuremath{\sim}1 GeV can lead to very dense axion clumps, with present density ${\mathrm{\ensuremath{\rho}}}_{\mathit{a}}$\ensuremath{\gtrsim}${10}^{\mathrm{\ensuremath{-}}8}$ g ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$. This is high enough for the… 

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We will discuss in a future paper the possibility that collapsing domain walls leave behind very dense clumps of non-relativistic axions