Vortices and Angular Momentum in Bose-Einstein-Condensed Cold Dark
  Matter Halos
  If cold dark matter elementary particles form a Bose-Einstein condensate,
their superfluidity may distinguish them from other forms of cold dark matter,
including creation of quantum vortices. We demonstrate here that such vortices
are favoured in strongly-coupled condensates, while this is not the case for
axions, which are generally presumed to form a Bose-Einstein condensate but are
effectively non-interacting.
