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arXiv · 2105.08948

Gamma-ray and Neutrino Signals from Accretion Disk Coronae of Active Galactic Nuclei

Yoshiyuki Inoue·Dmitry Khangulyan·Akihiro Doi
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Abstract

To explain X-ray spectra of active galactic nuclei (AGN), non-thermal activity in AGN coronae such as pair cascade models has been extensively discussed in the past literature. Although X-ray and gamma-ray observations in the 1990s disfavored such pair cascade models, recent millimeter-wave observations of nearby Seyferts establish the existence of weak non-thermal coronal activity. Besides, the IceCube collaboration reported NGC 1068, a nearby Seyfert, as the hottest spot in their 10-yr survey. These pieces of evidence are enough to investigate the non-thermal perspective of AGN coronae in depth again. This article summarizes our current observational understandings of AGN coronae and describes how AGN coronae generate high-energy particles. We also provide ways to test the AGN corona model with radio, X-ray, MeV gamma-ray, and high-energy neutrino observations.

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Yoshiyuki Inoue, Dmitry Khangulyan, Akihiro Doi. 2021-05-19. Gamma-ray and Neutrino Signals from Accretion Disk Coronae of Active Galactic Nuclei. https://doi.org/10.3390/galaxies9020036

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