Magnetic reconnection is often invoked as a source of highenergy particles, and in relativistic astrophysical systems it is regarded as a prime candidate for powering fast and bright flares. We present a novel analytical model—supported and benchmarked with largescale threedimensional kinetic particleincell simulations in electron–positron plasmas—that elucidates the physics governing the generation of powerlaw energy spectra in relativistic reconnection. Particles with Lorentz factor
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 largescale 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, Xray photons, and nonthermal protons is established in the reconnection region. Motivated by recent 3D particleincell 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). The proton spectrum is
 Award ID(s):
 2308944
 NSFPAR ID:
 10485963
 Publisher / Repository:
 DOI PREFIX: 10.3847
 Date Published:
 Journal Name:
 The Astrophysical Journal Letters
 Volume:
 961
 Issue:
 1
 ISSN:
 20418205
 Format(s):
 Medium: X Size: Article No. L14
 Size(s):
 Article No. L14
 Sponsoring Org:
 National Science Foundation
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