Constraints on ultracompact minihalos from extragalactic {\gamma}-ray background
Abstract
It has been proposed that ultracompact minihalos (UCMHs) might be formed in earlier epoch. If dark matter consists of Weakly Interacting Massive Particles (WIMPs), UCMHs can be treated as the {\gamma}-ray sources due to dark matter annihilation within them. In this paper, we investigate the contributions of UCMHs formed during three phase transi- tions (i.e., electroweak symmetry breaking, QCD confinement and e+ e- annihilation) to the extragalactic {\gamma}-ray background. Moreover, we use the Fermi-LAT observation data of the extragalactic {\gamma}-ray background to get the constraints on the current abundance of UCMHs produced during these phase transitions. We also compare these results with those obtained from Cosmic Microwave Background (CMB) observations and find that the constraints from the Fermi-LAT are more stringent than those from CMB
Keywords
Cite
@article{arxiv.1112.6229,
title = {Constraints on ultracompact minihalos from extragalactic {\gamma}-ray background},
author = {Yupeng Yang and Lei Feng and Xiaoyuan Huang and Xuelei Chen and Tan Lu and Hongshi Zong},
journal= {arXiv preprint arXiv:1112.6229},
year = {2011}
}
Comments
13 pages, 4 figures, 1 table