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arXiv · 1611.07905

Evidence for a break in the spectrum of astrophysical neutrinos

Luis A. Anchordoqui·Martin M. Block·Loyal Durand·Phuoc Ha·Jorge F. Soriano·Thomas J. Weiler
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Abstract

The announcement by the IceCube Collaboration of the observation of 53 astrophysical neutrino candidates in the energy range 0.03 \alt E_\nu/PeV \alt 2 has been greeted with a great deal of justified excitement. Herein we provide fits of single and a broken power-law energy-spectra to these high-energy starting events (HESEs). By comparing our statistical results from fits to (background-free) shower HESE data with the spectral shape of muon neutrinos recently reported by the IceCube Collaboration, we show that there is (3 \sigma) evidence for a break in the spectrum of astrophysical neutrinos. After that we use the fitted result to predict the rate of Glashow events (in the ~ 6.3 PeV region) and double-bang tau neutrino events (in the PeV region) just at the threshold of IceCube detection.

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Luis A. Anchordoqui, Martin M. Block, Loyal Durand, Phuoc Ha, Jorge F. Soriano, Thomas J. Weiler. 2016-11-23. Evidence for a break in the spectrum of astrophysical neutrinos. https://doi.org/10.1103/physrevd.95.083009

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