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arXiv · 1807.08794

Neutrino emission from the direction of the blazar TXS 0506+056 prior to the IceCube-170922A alert

IceCube Collaboration
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Abstract

A high-energy neutrino event detected by IceCube on 22 September 2017 was coincident in direction and time with a gamma-ray flare from the blazar TXS 0506+056. Prompted by this association, we investigated 9.5 years of IceCube neutrino observations to search for excess emission at the position of the blazar. We found an excess of high-energy neutrino events with respect to atmospheric backgrounds at that position between September 2014 and March 2015. Allowing for time-variable flux, this constitutes 3.5{\sigma} evidence for neutrino emission from the direction of TXS 0506+056, independent of and prior to the 2017 flaring episode. This suggests that blazars are the first identifiable sources of the high-energy astrophysical neutrino flux.

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IceCube Collaboration. 2018-07-23. Neutrino emission from the direction of the blazar TXS 0506+056 prior to the IceCube-170922A alert. https://doi.org/10.1126/science.aat2890

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