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Abstract Any dark matter spikes surrounding black holes in our Galaxy are sites of significant dark matter annihilation, leading to a potentially detectable neutrino signal. In this paper we examine 10 - 10 5 M ⊙ black holes associated with dark matter spikes that formed in early minihalos and still exist in our Milky Way Galaxy today, in light of neutrino data from the ANTARES [1] and IceCube [2] detectors. In various regions of the sky, we determine the minimum distance away from the solar system that a dark matter spike must be in order to have not been detected as a neutrino point source for a variety of representative dark matter annihilation channels. Given these constraints on the distribution of dark matter spikes in the Galaxy, we place significant limits on the formation of the first generation of stars in early minihalos — stronger than previous limits from gamma-ray searches in Fermi Gamma-Ray Space Telescope data. The larger black holes considered in this paper may arise as the remnants of Dark Stars after the dark matter fuel is exhausted; thus neutrino observations may be used to constrain the properties of Dark Stars. The limits are particularly strong for heavier WIMPs. For WIMP masses ∼ 5TeV, we show that ≲ 10 % of minihalos can host first stars that collapse into BHs larger than 10 3 M ⊙ .
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Sterile Neutrino/Dark Fermion Dark Matter: Searches in the X-Ray Sky, the Nuclear Physics Laboratory and in Galaxy Formation
The possibility of dark matter being a particle involved in the generation of neutrino mass has been of interest for over 25 years. Sterile neutrinos—or in the contemporary parlance—dark fermions, are among the simplest and most cited particles which can provide a mechanism for neutrino mass. If one particle of this class has a small mixing, it can be quasi-thermally or nonthermally produced in the early Universe, affect cosmological structure formation, and be detected by X-ray telescopes or laboratory nuclear experiments. A candidate line was detected in 2014, and I review the status of the line and its implications for galaxy formation, proposals for future observations, and laboratory detection.
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- Award ID(s):
- 1915005
- PAR ID:
- 10347853
- Date Published:
- Journal Name:
- Astrophysics and space science proceedings
- ISSN:
- 1570-6591
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/978-3-030-31593-1_1
