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Title: Observation of high-energy neutrinos from the Galactic plane

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth’s atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

 
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Award ID(s):
1847827 2209445
PAR ID:
10493540
Author(s) / Creator(s):
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Corporate Creator(s):
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science
Volume:
380
Issue:
6652
ISSN:
0036-8075
Page Range / eLocation ID:
1338 to 1343
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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