English

The dark matter is mostly an axion BEC

Cosmology and Nongalactic Astrophysics 2015-03-17 v1

Abstract

Axions differ from ordinary cold dark matter, such as WIMPs or sterile neutrinos, because they form a Bose-Einstein condensate (BEC). As a result, axions accreting onto a galactic halo fall in with net overall rotation. In contrast, ordinary CDM accretes onto galactic halos with an irrotational velocity field. The inner caustics are different in the two cases. It is shown that if the dark matter is axions, the phase space structure of the halos of isolated disk galaxies, such as the Milky Way, is precisely that of the caustic ring model for which observational support exists. The other dark matter candidates predict a far more chaotic phase space structure for galactic halos.

Keywords

Cite

@article{arxiv.1012.1553,
  title  = {The dark matter is mostly an axion BEC},
  author = {Pierre Sikivie},
  journal= {arXiv preprint arXiv:1012.1553},
  year   = {2015}
}

Comments

11 pages, invited talk at the IDM2010 International Conference on the Identification of Dark Matter, Montpellier, France, July 26-30, 2010

R2 v1 2026-06-21T16:54:56.302Z