TY - JOUR
T1 - Current constraints from cosmogenic neutrinos on the fraction of protons in UHECRs
AU - van Vliet, Arjen
AU - Batista, Rafael Alves
AU - Hörandel, Jörg R.
N1 - Funding Information:
AvV acknowledges financial support from the NWO Astroparticle Physics grant WARP and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant No. 646623). RAB is supported by grant #2017/12828-4, São Paulo Research Foundation (FAPESP).
Funding Information:
AvV acknowledges financial support from the NWO Astroparticle Physics grant WARP and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant No. 646623). RAB is supported by grant #2017/12828-4, S?o Paulo Research Foundation (FAPESP).
Publisher Copyright:
© Owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0).
PY - 2019
Y1 - 2019
N2 - Cosmogenic neutrinos are created when ultra-high-energy cosmic rays (UHECRs) interact with extragalactic photon backgrounds. In general, the expected flux of these cosmogenic neutrinos depends on multiple parameters, describing the sources and propagation of UHECRs. In our recent paper [1], we show that a 'sweet spot'occurs at a neutrino energy of E? ~ 1 EeV. At that energy the flux mainly depends on two parameters, the source evolution and the fraction of protons in UHECRs at Earth for Ep & 30 EeV. Therefore, with current upper limits on the cosmogenic neutrino flux at E? ~ 1 EeV and assuming a certain source class, a constraint on the composition of UHECRs can be obtained. This constraint is independent of hadronic interaction models and indicates that the combination of a large proton fraction and a strong source evolution is disfavored. Upcoming neutrino experiments will be able to constrain the fraction of protons in UHECRs even further, and for any realistic model for the evolution of UHECR sources.
AB - Cosmogenic neutrinos are created when ultra-high-energy cosmic rays (UHECRs) interact with extragalactic photon backgrounds. In general, the expected flux of these cosmogenic neutrinos depends on multiple parameters, describing the sources and propagation of UHECRs. In our recent paper [1], we show that a 'sweet spot'occurs at a neutrino energy of E? ~ 1 EeV. At that energy the flux mainly depends on two parameters, the source evolution and the fraction of protons in UHECRs at Earth for Ep & 30 EeV. Therefore, with current upper limits on the cosmogenic neutrino flux at E? ~ 1 EeV and assuming a certain source class, a constraint on the composition of UHECRs can be obtained. This constraint is independent of hadronic interaction models and indicates that the combination of a large proton fraction and a strong source evolution is disfavored. Upcoming neutrino experiments will be able to constrain the fraction of protons in UHECRs even further, and for any realistic model for the evolution of UHECR sources.
UR - http://www.scopus.com/inward/record.url?scp=85086262938&partnerID=8YFLogxK
M3 - Conference article
AN - SCOPUS:85086262938
SN - 1824-8039
VL - 358
JO - Proceedings of Science
JF - Proceedings of Science
T2 - 36th International Cosmic Ray Conference, ICRC 2019
Y2 - 24 July 2019 through 1 August 2019
ER -