Relaxation times for Bose-Einstein condensation in axion miniclusters

Academic Article

Abstract

  • We study the Bose condensation of scalar dark matter in the presence of both gravitational and self-interactions. Axions and other scalar dark matter in gravitationally bound miniclusters or dark matter halos are expected to condense into Bose-Einstein condensates called Bose stars. This process has been shown to occur through attractive self-interactions of the axion-like particles or through the field's self gravitation. We show that in the high-occupancy regime of scalar dark matter, the Boltzmann collision integral does not describe either gravitaitonal or self-interactions, and derive kinetic equations valid for these interactions. We use this formalism to compute relaxation times for the Bose-Einstein condensation, and find that condensation into Bose stars could occur within the lifetime of the universe. The self-interactions reduce the condensation time only when they are very strong.
  • Authors

  • Kirkpatrick, Kay
  • Mirasola, Anthony E
  • Prescod-Weinstein, Chanda
  • Status

    Publication Date

  • November 9, 2020
  • Published In

  • Physical Review D  Journal
  • Keywords

  • astro-ph.CO
  • hep-ph
  • Digital Object Identifier (doi)

    Start Page

  • 103012
  • Volume

  • 102
  • Issue

  • 10