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Title: TeV Neutrinos and Hard X-Rays from Relativistic Reconnection in the Corona of NGC 1068
The recent discovery of astrophysical neutrinos from the Seyfert galaxy NGC 1068 suggests the presence of nonthermal protons within a compact “coronal” region close to the central black hole. The acceleration mechanism of these nonthermal protons remains elusive. We show that a large-scale magnetic reconnection layer, of the order of a few gravitational radii, may provide such a mechanism. In such a scenario, rough energy equipartition between magnetic fields, X-ray photons, and nonthermal protons is established in the reconnection region. Motivated by recent 3D particle-in-cell simulations of relativistic reconnection, we assume that the spectrum of accelerated protons is a broken power law, with the break energy being constrained by energy conservation (i.e., the energy density of accelerated protons is at most comparable to the magnetic energy density). Protons above the break lose most of their energy within the reconnection layer via photohadronic collisions with the coronal X-rays, producing a neutrino signal in good agreement with the recent observations. Gamma rays injected in photohadronic collisions are cascaded to lower energies, sustaining the population of electron–positron pairs that makes the corona moderately Compton thick.  more » « less
Award ID(s):
2308944
PAR ID:
10514143
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
The Astrophysical Journal Letters
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
961
Issue:
1
ISSN:
2041-8205
Page Range / eLocation ID:
L14
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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