Constraining condensate dark matter in galaxy clusters

TL;DR

This paper constrains the scattering length parameters of Bose-Einstein condensate dark matter using galaxy cluster radii, revealing significantly larger values than those found in galaxies, and compares orbital velocity curves in expanding and non-expanding scenarios.

Contribution

It applies a galaxy-scale method to galaxy clusters to constrain dark matter properties, extending previous work and incorporating cosmological expansion effects.

Findings

Scattering lengths are five orders of magnitude larger than in galactic cases.

Cluster radii data constrains dark matter particle mass in the range 10^{-6} to 10^{-4} eV.

Orbital velocity curves differ between expanding and non-expanding models.

Abstract

We constrain scattering length parameters in a Bose-Einstein condensate dark matter model by using galaxy clusters radii, with the implementation of a method previously applied to galaxies. At the present work, we use a sample of 114 clusters radii in order to obtain the scattering lengths associated with a dark matter particle mass in the range $10^{-6}-10^{-4}\, {\rm eV}$. We obtain scattering lengths that are five orders of magnitude larger than the ones found in the galactic case, even when taking into account the cosmological expansion in the cluster scale by means of the introduction of a small cosmological constant. We also construct and compare curves for the orbital velocity of a test particle in the vicinity of a dark matter cluster in both the expanding and the non-expanding cases.