Highly-boosted dark matter and cutoff for cosmic-ray neutrinos through neutrino portal

Wen Yin,B Pattison,Y Itow,H Menjo,T Sako

doi:10.1051/epjconf/201920804003

Abstract

We study the cutoff for the cosmic-ray neutrino, set by the scattering with cosmic background neutrinos into dark sector particles through a neutrino portal interaction. We find that a large interaction rate is still viable, when the dark sector particles are mainly coupled to the τ-neutrino, so that the neutrino mean free path can be reduced to be O(10) Mpc over a wide energy range. If stable enough, the dark sector particle, into which most of the cosmic-ray neutrino energy is transferred, can travel across the Universe and reach the earth. The dark sector particle can carry the energy as large as O(EeV) if it originates from a cosmogenic neutrino.

Highlights

The cosmogenic neutrinos are known as a “guaranteed" flux of cosmic ray neutrinos, which are generated through photo-pion production, where the interaction is between ultra-high cosmic rays (UHECRs) and ambient photon backgrounds [1], This interaction was first proposed to set a cutoff for UHECRs and the cutoff as well as the UHECRs have already been observed [2, 3]
It was pointed out that a cutoff for the cosmic-ray neutrino can be set through its scattering with cosmic background neutrinos (CνB) into the dark sector particles through the neutrino-portal interaction by using an effective theory approach [7]. (For other models or other scattering processes affecting cosmic-ray neutrinos, see e.g. Refs [8,9,10,11].) the Universe could be opaque to the cosmic-ray neutrino
We found that the cosmogenic neutrino flux to the earth can be significantly reduced due to the neutrino portal interaction

Summary

Introduction

The cosmogenic neutrinos are known as a “guaranteed" flux of cosmic ray neutrinos, which are generated through photo-pion production, where the interaction is between ultra-high cosmic rays (UHECRs) and ambient photon backgrounds [1], This interaction was first proposed to set a cutoff for UHECRs and the cutoff as well as the UHECRs have already been observed [2, 3]. We study the propagation of cosmic-ray neutrinos with Dirac neutrino portal interaction, where the right-handed neutrinos are Dirac-type particles. Since the energy of the cosmic-ray neutrinos is transferred into the dark matter, there could be a flux of highly-boosted dark matter in the universe. They reach the earth instead of the cosmic-ray neutrinos which may be tested in various neutrino observatories

Dirac neutrino portal interaction

Cutoff for neutrino flux

Highly boosted dark matter

Discussion

Conclusions