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DOE OSTI · 2447658

Upper limits on the cosmic neutrino background from cosmic rays

Císcar-Monsalvatje, Mar·Herrera, Gonzalo·Shoemaker, Ian M.
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Abstract

Extragalactic and galactic cosmic rays scatter with the cosmic neutrino background during propagation to Earth, yielding a flux of relic neutrinos boosted to larger energies. If an overdensity of relic neutrinos is present in galaxies, and neutrinos are massive enough, this flux might be detectable by high-energy neutrino experiments. For a lightest neutrino of mass 𝑚 𝜈 ∼0.1 eV, we find an upper limit on the local relic neutrino overdensity of ∼10 13 and an upper limit on the relic neutrino overdensity at TXS 0506 + 056 of ∼10 10 . Future experiments like GRAND or IceCube-Gen2 could improve these bounds by orders of magnitude.

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Císcar-Monsalvatje, Mar, Herrera, Gonzalo, Shoemaker, Ian M.. 2024-09-23. Upper limits on the cosmic neutrino background from cosmic rays. https://doi.org/10.1103/physrevd.110.063036

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