The nature of dark matter, the invisible substance making up over 80% of the matter in the universe, is one of the most fundamental mysteries of modern physics. Ultralight bosons such as axions, axion-like particles, or dark photons could make up most of the dark matter. Couplings between such bosons and nuclear spins may enable their direct detection via nuclear magnetic resonance (NMR) spectroscopy: As nuclear spins move through the galactic dark-matter halo, they couple to dark matter and behave as if they were in an oscillating magnetic field, generating a dark-matter–driven NMR signal. As part of the cosmic axion spin precession experiment (CASPEr), an NMR-based dark-matter search, we use ultralow-field NMR to probe the axion-fermion “wind” coupling and dark-photon couplings to nuclear spins. No dark matter signal was detected above background, establishing new experimental bounds for dark matter bosons with masses ranging from 1.8 × 10 −16 to 7.8 × 10 −14 eV.
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Constraints on light decaying dark matter candidates from 16 yr of INTEGRAL/SPI observations
ABSTRACT We apply the recently developed analysis of 16 yr of INTEGRAL/SPI data including a dark matter spatial template to derive bounds on dark matter candidates lighter than weakly interacting massive particles (like sterile neutrinos or axion-like particles) decaying into line or continuum electromagnetic final state channels. The bounds obtained are the strongest to date for dark matter masses between ∼60 keV and ∼16 MeV experiencing two-body decays producing photon lines.
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- Award ID(s):
- 2011759
- NSF-PAR ID:
- 10437792
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 520
- Issue:
- 3
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 4167 to 4172
- 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/10.1093/mnras/stad457
