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Title: Constraining decaying very heavy dark matter from galaxy clusters with 14 year Fermi-LAT data
Abstract Galaxy clusters are promising targets for indirect detection of dark matter thanks to the large dark matter content. Using 14 years ofFermi-LAT data from seven nearby galaxy clusters, we obtain constraints on the lifetime of decaying very heavy dark matter particles with masses ranging from 103GeV to 1016GeV. We consider a variety of decaying channels and calculate prompt gamma rays and electrons/positrons from the dark matter. Furthermore, we take into account electromagnetic cascades induced by the primary gamma rays and electrons/positrons, and search for the resulting gamma-ray signals from the directions of the galaxy clusters. We adopt a Navarro-Frenk-White profile of the dark matter halos, and use the profile likelihood method to set lower limits on the dark matter lifetime at a 95% confidence level. Our results are competitive with those obtained through other gamma-ray observations of galaxy clusters and provide complementary constraints to existing indirect searches for decaying very heavy dark matter.  more » « less
Award ID(s):
2108466 2108467
PAR ID:
10536973
Author(s) / Creator(s):
; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Cosmology and Astroparticle Physics
Volume:
2024
Issue:
03
ISSN:
1475-7516
Page Range / eLocation ID:
024
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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