Journal
PHYSICS OF THE DARK UNIVERSE
Volume 33, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.dark.2021.100874
Keywords
Dark matter; Galaxy groups; Radial acceleration relation; Constant halo surface density
Categories
Ask authors/readers for more resources
The study found that the dark matter halo surface density is not a universal constant for all dark matter dominated systems. There are significant differences in surface density for galaxy groups and clusters, as well as noticeable discrepancies in residual scatter in the radial acceleration relation.
The dark matter halo surface density, given by the product of the dark matter core radius (rc) and core density (rho c) has been shown to be a constant for a wide range of isolated galaxy systems. Here, we carry out a test of this ansatz using a sample of 17 relaxed galaxy groups observed using Chandra and XMM-Newton, as an extension of our previous analysis with galaxy clusters. We find that rho c proportional to r(-0.17)(-1.35)(+0.16), with an intrinsic scatter of about 27.3%, which is about 1.5 times larger than that seen for galaxy clusters. Our results thereby indicate that the surface density is discrepant with respect to scale invariance by about 2 sigma, and its value is about four times greater than that for galaxies. Therefore, the elevated values of the halo surface density for groups and clusters indicate that the surface density cannot be a universal constant for all dark matter dominated systems. Furthermore, we also implement a test of the radial acceleration relation for this group sample. We find that the residual scatter in the radial acceleration relation is about 0.32 dex and a factor of three larger than that obtained using galaxy clusters. The acceleration scale which we obtain is in-between that seen for galaxies and clusters. (C) 2021 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available