Gravitational Lensing Signatures of Axion Dark Matter Minihalos in Highly Magnified Stars

  title={Gravitational Lensing Signatures of Axion Dark Matter Minihalos in Highly Magnified Stars},
  author={Liang Dai and Jordi Miralda-Escud'e},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
Axions are a viable candidate for Cold Dark Matter (CDM) which should generically form minihalos of sub-planetary masses from white-noise isocurvature density fluctuations if the Peccei-Quinn phase transition occurs after inflation. Despite being denser than the larger halos formed out of adiabatic fluctuations from inflation, axion minihalos have surface densities much smaller than the critical value required for gravitational lensing to produce multiple images or high magnification, and hence… 

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