Abstract
Motivated by the fact that, so far, the whole body of evidence for dark matter is of gravitational origin, we study the decays of dark matter into Standard Model particles mediated by gravity portals, i. e., through nonminimal gravitational interactions of dark matter. We investigate the decays in several widely studied frameworks of scalar and fermionic dark matter where the dark matter is stabilized in flat spacetime via global symmetries. We find that the constraints on the scalar singlet dark matter candidate are remarkably strong and exclude large regions of the parameter space, suggesting that an additional stabilizing symmetry should be in place. In contrast, the scalar doublet and the fermionic singlet candidates are naturally protected against too-fast decays by gauge and Lorentz symmetry, respectively. For a nonminimal coupling parameter epsilon similar to O(1), decays through the gravity portal are consistent with observations if the dark matter mass is smaller than similar to 10(5) GeV, for the scalar doublet, and similar to 10(6) GeV, for the fermionic singlet.
Item Type: | Journal article |
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Faculties: | Physics |
Subjects: | 500 Science > 530 Physics |
ISSN: | 2470-0010 |
Language: | English |
Item ID: | 55695 |
Date Deposited: | 14. Jun 2018, 10:00 |
Last Modified: | 04. Nov 2020, 13:35 |