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arXiv · 2306.00960

Hard X-ray emission from blazars associated with high-energy neutrinos

A. V. Plavin·R. A. Burenin·Y. Y. Kovalev·A. A. Lutovinov·A. A. Starobinsky·S. V. Troitsky·E. I. Zakharov
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Abstract

Bright blazars were found to be prominent neutrino sources, and a number of IceCube events were associated with them. Evaluating high-energy photon emission of such blazars is crucial for better understanding of the processes and regions where neutrinos are produced. Here, we focus on hard X-ray emission observed by the SRG/ART-XC telescope, by the Swift/BAT imager, and by the INTEGRAL/IBIS telescope. Their energy range ~10 keV is well-suited for probing photons that potentially participate in neutrino production by interacting with ultrarelativistic protons. We find that neutrino-associated blazars tend to demonstrate remarkably strong X-ray emission compared to other VLBI blazars in the sky. Both neutrinos and hard X-rays are found to come from blazars at cosmological distances z ~ 1, and are boosted by relativistic beaming that makes it possible to detect them on Earth. Our results suggest that neutrinos are produced within compact blazar jets, with target X-ray photons emitted from accelerated jet regions.

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A. V. Plavin, R. A. Burenin, Y. Y. Kovalev, A. A. Lutovinov, A. A. Starobinsky, S. V. Troitsky, E. I. Zakharov. 2023-06-01. Hard X-ray emission from blazars associated with high-energy neutrinos. https://doi.org/10.1088/1475-7516%2F2024%2F05%2F133

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