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.
@article{arxiv.2306.00960,
title = {Hard X-ray emission from blazars associated with high-energy neutrinos},
author = {A. V. Plavin and R. A. Burenin and Y. Y. Kovalev and A. A. Lutovinov and A. A. Starobinsky and S. V. Troitsky and E. I. Zakharov},
journal= {arXiv preprint arXiv:2306.00960},
year = {2024}
}