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DOE OSTI · 3008821

Diffuse boosted cosmic neutrino background

Herrera, Gonzalo [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Univ. of Tokyo (Japan). Kavli Institute for the Physics and Mathematics of the Universe (WPI)] (ORCID:0000000192508597)·Horiuchi, Shunsaku [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Univ. of Tokyo (Japan). Kavli Institute for the Physics and Mathematics of the Universe (WPI)] (ORCID:0000000161426556)·Qi, Xiaolin [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Univ. of Tokyo (Japan). Kavli Institute for the Physics and Mathematics of the Universe (WPI)] (ORCID:0009000297470334)
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Abstract

Energetic cosmic rays scatter off the cosmic neutrino background throughout the history of the Universe, yielding a diffuse flux of cosmic relic neutrinos boosted to high energies. We calculate this flux under different assumptions of the cosmic-ray flux spectral slope and redshift evolution. The nonobservation of the diffuse flux of boosted relic neutrinos with current high-energy neutrino experiments already excludes an average cosmic neutrino background overdensity larger than ∼10 4 over cosmological distances. We discuss the future detectability of the diffuse flux of boosted relic neutrinos in light of neutrino overdensity estimates and cosmogenic neutrino backgrounds.

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Herrera, Gonzalo [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Univ. of Tokyo (Japan). Kavli Institute for the Physics and Mathematics of the Universe (WPI)] (ORCID:0000000192508597), Horiuchi, Shunsaku [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Univ. of Tokyo (Japan). Kavli Institute for the Physics and Mathematics of the Universe (WPI)] (ORCID:0000000161426556), Qi, Xiaolin [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Univ. of Tokyo (Japan). Kavli Institute for the Physics and Mathematics of the Universe (WPI)] (ORCID:0009000297470334). 2025-03-05. Diffuse boosted cosmic neutrino background. https://doi.org/10.1103/physrevd.111.063016

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