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arXiv · 2404.05690

The neutrino background from non-jetted active galactic nuclei

P. Padovani·R. Gilli·E. Resconi·C. Bellenghi·F. Henningsen
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Abstract

Aims. We calculate the contribution to the neutrino background from the non-jetted active galactic nuclei (AGN) population following the recent IceCube association of TeV neutrinos with NGC 1068. Methods. We exploit our robust knowledge of the AGN X-ray luminosity function and evolution and convert it to the neutrino band by using NGC 1068 as a benchmark and a theoretically motivated neutrino spectrum. Results. The resulting neutrino background up to redshift 5 does not violate either the IceCube diffuse flux or the upper bounds for non-jetted AGN, although barely so. This is consistent with a scenario where the latter class makes a substantial contribution mostly below 1 PeV, while jetted AGN, i.e. blazars, dominate above this energy, in intriguing agreement with the dip in the neutrino data at ~ 300 TeV. More and better IceCube data on Seyfert galaxies will allow us to constrain the fraction of neutrino emitters among non-jetted AGN.

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P. Padovani, R. Gilli, E. Resconi, C. Bellenghi, F. Henningsen. 2024-04-08. The neutrino background from non-jetted active galactic nuclei. https://doi.org/10.1051/0004-6361/202450025

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