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Abstract In this work, we present the results of searches for signatures of dark matter decay or annihilation into Standard Model particles, and secret neutrino interactions with dark matter.Neutrinos could be produced in the decay or annihilation of galactic or extragalactic dark matter.Additionally, if an interaction between dark matter and neutrinos exists then dark matter will interact with extragalactic neutrinos.In particular galactic dark matter will induce an anisotropy in the neutrino sky if this interaction is present.We use seven and a half years of the High-Energy Starting Event (HESE) sample data, which measures neutrinos in the energy range of approximately 60 TeV to 10 PeV, to study these phenomena.This all-sky event selection is dominated by extragalactic neutrinos.For dark matter of ∼ 1 PeV in mass, we constrain the velocity-averaged annihilation cross section to be smaller than 10-23cm3/s for the exclusiveμ+μ-channel and 10-22cm3/s for the bb̅ channel.For the same mass, we constrain the lifetime of dark matter to be larger than 1028s for all channels studied, except for decaying exclusively to bb̅ where it is bounded to be larger than 1027s.Finally, we also search for evidence of astrophysical neutrinos scattering on galactic dark matter in two scenarios.For fermionic dark matter with a vector mediator, we constrain the dimensionless coupling associated with this interaction to be less than 0.1 for dark matter mass of 0.1 GeV and a mediator mass of 10-4GeV.In the case of scalar dark matter with a fermionic mediator, we constrain the coupling to be less than 0.1 for dark matter and mediator masses below 1 MeV.
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Dark matter freeze-in with a heavy mediator: beyond the EFT approach
A bstract We study dark matter freeze-in scenarios where the mass of the mediator particle that couples dark matter to the Standard Model is larger than the reheat temperature, T RH , in the early Universe. In such setups, the standard approach is to work with an effective field theory (EFT) where the mediator is integrated out. We examine the validity of this approach in various generic s- and t-channel mediator frameworks. We find that the EFT approach breaks down when the mediator mass is between one to two orders of magnitude larger than T RH due to various effects such as s-channel resonance, a small thermally-suppressed abundance of the mediator, or decays of Standard Model particles through loops induced by the mediator. This highlights the necessity of including these contributions in such dark matter freeze-in studies. We also discuss the collider phenomenology of the heavy mediators, which is qualitatively different from standard freeze-in scenarios. We highlight that, due to the low T RH , the Standard Model-dark matter coupling in these scenarios can be relatively larger than in standard freeze-in scenarios, improving the testability prospects of these setups.
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- Award ID(s):
- 1915852
- PAR ID:
- 10402495
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2022
- Issue:
- 9
- ISSN:
- 1029-8479
- 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/JHEP09(2022)083
