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arXiv · 2211.09631

Growing evidence for high-energy neutrinos originating in radio blazars

A. V. Plavin·Y. Y. Kovalev·Y. A. Kovalev·S. V. Troitsky
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Abstract

Evidence for bright radio blazars being high-energy neutrino sources was found in recent years. However, specifics of how and where these particles get produced still need to be determined. In this paper, we add 14 new IceCube events from 2020-2022 to update our analysis of the neutrino-blazars connection. We test and refine earlier findings by utilising the total of 71 track-like high-energy IceCube events from 2009-2022. We correlate them with the complete sample of 3412 extragalactic radio sources selected by their compact radio emission. We demonstrate that neutrinos are statistically associated with radio-bright blazars with a post-trial p-value of 3*10^-4. In addition to this statistical study, we confirm previous individual neutrino-blazar associations, find and discuss several new ones. Notably, PKS 1741-038 was selected earlier and had a second neutrino detected from its direction in 2022; PKS 0735+168 has experienced a major flare across the whole electromagnetic spectrum coincidently with a neutrino arrival from that direction in 2021.

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A. V. Plavin, Y. Y. Kovalev, Y. A. Kovalev, S. V. Troitsky. 2022-11-17. Growing evidence for high-energy neutrinos originating in radio blazars. https://doi.org/10.1093/mnras%2Fstad1467

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