skip to main content


Title: Multi-PeV Signals from a New Astrophysical Neutrino Flux beyond the Glashow Resonance

The IceCube neutrino discovery was punctuated by three showers with E ν ≈ 1–2 PeV. Interest is intense in possible fluxes at higher energies, though a deficit of E ν ≈ 6 PeV Glashow resonance events implies a spectrum that is soft and/or cutoff below ~ few PeV. However, IceCube recently reported a through-going track depositing 2.6 ± 0.3 PeV. A muon depositing so much energy can imply E νμ ≳ 10 PeV. Alternatively, we find a tau can deposit this much energy, requiring E ντ ~ 10× higher. Here, we show that extending soft spectral fits from TeV-PeV data is unlikely to yield such an event, while an ~ E v -2 flux predicts excessive Glashow events. These instead hint at a new flux, with the hierarchy of ν μ and ν τ energies implying astrophysical neutrinos at E ν ~ 100 PeV if a tau. We address implications for ultrahigh-energy cosmic-ray and neutrino origins.
 [1] ;  [2]
  1. Stanford Univ., CA (United States). Dept. of Physics and Kavli Inst. for Particle Astrophysics and Cosmology; SLAC National Accelerator Lab., Menlo Park, CA (United States)
  2. Johannes Gutenberg Univ., Mainz (Germany). PRISMA Cluster of Excellence and Mainz Inst. for Theoretical Physics
Publication Date:
Grant/Contract Number:
AC02-76SF00515; EXC-1098; KO 4820/1-1; FOR 2239; 637506
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 120; Journal Issue: 24; Journal ID: ISSN 0031-9007
American Physical Society (APS)
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE; Univ. of Washington, Seattle, WA (United States). Inst. for Nuclear Theory (INT); Kavli Foundation; German Research Foundation (DFG); European Research Council (ERC)
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; cosmic ray and astroparticle detectors; cosmic ray and astroparticles; extrasolar neutrino astronomy; particle astrophyiscs
OSTI Identifier: