Can QCD axion stars explain Subaru HSC microlensing?

  title={Can QCD axion stars explain Subaru HSC microlensing?},
  author={Enrico D. Schiappacasse and Tsutomu. T. Yanagida},
  journal={Physical Review D},
A non-negligible fraction of the QCD axion dark matter may form gravitationally bound Bose Einstein condensates, which are commonly known as axion stars or axion clumps. Such astrophysical objects have been recently proposed as the cause for the single candidate event reported by Subaru HSC microlensing search in the Andromeda galaxy. Depending on the breaking scale of the Peccei–Quinn symmetry and the details of the dark matter scenario, QCD axion clumps may form via gravitational condensation… Expand
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