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Probing the origin of ultra-high-energy cosmic rays with neutrinos in the EeV energy range using the Pierre Auger Observatory

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Journal of Cosmology and Astroparticle Physics
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A. Aab
A. Aab
A. Aab
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P. Abreu
P. Abreu
P. Abreu
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Marco Aglietta at INFN - Istituto Nazionale di Fisica Nucleare
Marco Aglietta
I.F.M. Albuquerque
I.F.M. Albuquerque
I.F.M. Albuquerque
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Abstract

Neutrinos with energies above 1017 eV are detectable with the Surface Detector Array of the Pierre Auger Observatory. The identification is efficiently performed for neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for Earth-skimming τ neutrinos with nearly tangential trajectories relative to the Earth. No neutrino candidates were found in ~ 14.7 years of data taken up to 31 August 2018. This leads to restrictive upper bounds on their flux. The 90% C.L. single-flavor limit to the diffuse flux of ultra-high-energy neutrinos with an Eν−2 spectrum in the energy range 1.0 × 1017 eV –2.5 × 1019 eV is E2 dNν/dEν < 4.4 × 10−9 GeV cm−2 s−1 sr−1, placing strong constraints on several models of neutrino production at EeV energies and on the properties of the sources of ultra-high-energy cosmic rays.
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JCAP10(2019)022
ournal of
Cosmology and Astroparticle Physics
An IOP and SISSA journal
J
Probing the origin of ultra-high-energy
cosmic rays with neutrinos in the EeV
energy range using the Pierre Auger
Observatory
The Pierre Auger collaboration
E-mail: auger spokespersons@fnal.gov
Received June 19, 2019
Accepted September 5, 2019
Published October 8, 2019
Abstract. Neutrinos with energies above 1017 eV are detectable with the Surface Detec-
tor Array of the Pierre Auger Observatory. The identification is efficiently performed for
neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for
Earth-skimming τneutrinos with nearly tangential trajectories relative to the Earth. No
neutrino candidates were found in ∼14.7 years of data taken up to 31 August 2018. This
leads to restrictive upper bounds on their flux. The 90% C.L. single-flavor limit to the diffuse
flux of ultra-high-energy neutrinos with an E−2
νspectrum in the energy range 1.0×1017 eV–
2.5×1019 eV is E2dNν/dEν<4.4×10−9GeV cm−2s−1sr−1, placing strong constraints on
several models of neutrino production at EeV energies and on the properties of the sources
of ultra-high-energy cosmic rays.
Keywords: cosmic ray experiments, cosmological neutrinos, ultra high energy cosmic rays,
neutrino astronomy
ArXiv ePrint: 1906.07422
c
2019 IOP Publishing Ltd and Sissa Medialab https://doi.org/10.1088/1475-7516/2019/10/022
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