Loading…
Consequences of Short-Range Interactions between Dark Matter and Protons in Galaxy Clusters
Protons gain energy in short-range collisions with heavier dark matter particles (DMPs) of comparable velocity dispersion. We examine the conditions under which the heating of baryons by scattering off DMPs can offset radiative cooling in the cores of galaxy clusters. Collisions with a constant mome...
Saved in:
Published in: | The Astrophysical journal 2006-07, Vol.645 (2), p.950-954 |
---|---|
Main Authors: | , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | Protons gain energy in short-range collisions with heavier dark matter particles (DMPs) of comparable velocity dispersion. We examine the conditions under which the heating of baryons by scattering off DMPs can offset radiative cooling in the cores of galaxy clusters. Collisions with a constant momentum transfer cross section, s sub(xp), independent of the relative velocity of the colliding particles, cannot produce stable thermal balance. In this case, avoiding an unrealistic increase of the central temperatures yields the upper bound s sub(xp) < 10 super(-25) cm super(2)(m sub(x)/m sub(p)), where m sub(x) and m sub(p) are the DMP and proton mass, respectively. However, in clusters with T > 2 keV, a stable balance can be achieved for a power-law dependence on the relative velocity, V, of the form s sub(xp) 8 V super(a), with a -3. An advantage of this heating mechanism is that it preserves the metal gradients observed in clusters. |
---|---|
ISSN: | 0004-637X 1538-4357 |
DOI: | 10.1086/504505 |