Galactic cold dark matter as a Bose-Einstein condensate of WISPs

Abstract

We propose here the dark matter content of galaxies as a cold bosonic fluid composed of Weakly Interacting Slim Particles (WISPs), represented by spin-0 axion-like particles and spin-1 hidden bosons, thermalized in the Bose-Einstein condensation state and bounded by their self-gravitational potential. We analyze two zero-momentum configurations: the polar phases in which spin alignment of two neighbouring particles is anti-parallel and the ferromagnetic phases in which every particle spin is aligned in the same direction. Using the mean field approximation we derive the Gross-Pitaevskii equations for both cases, and, supposing the dark matter to be a polytropic fluid, we describe the particles density profile as Thomas-Fermi distributions characterized by the halo radii and in terms of the scattering lengths and mass of each particle. By comparing this model with data obtained from 42 spiral galaxies and 19 Low Surface Brightness (LSB) galaxies, we constrain the dark matter particle mass to the range $10^{-6}-10^{-4}eV$ and we find the lower bound for the scattering length to be of the order $10^{-14}fm$.

13 pages; 6 figures; references added; v.3: typo corrected in the abstract, published in JCAP

References in corpus (6)

• Dark Matter Candidates from Particle Physics and Methods of Detection
• Constraints on the Self-Interaction Cross-Section of Dark Matter from Numerical Simulations of the Merging Galaxy Cluster 1E 0657-5
• Bose-Einstein Condensation of Dark Matter Axions
• Dynamical Centers and Non-Circular Motions in THINGS Galaxies: Implications for Dark Matter Halos
• The Caustic Ring Model of the Milky Way Halo
• Optimizing Light-Shining-through-a-Wall Experiments for Axion and other WISP Searches