TeV neutrinos and hard X-rays from relativistic reconnection in the corona of NGC 1068

التفاصيل البيبلوغرافية
العنوان: TeV neutrinos and hard X-rays from relativistic reconnection in the corona of NGC 1068
المؤلفون: Fiorillo, Damiano F. G., Petropoulou, Maria, Comisso, Luca, Peretti, Enrico, Sironi, Lorenzo
المصدر: The Astrophysical Journal Letters, Volume 961, Number 1, January 2024
سنة النشر: 2023
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - High Energy Astrophysical Phenomena
الوصف: The recent discovery of astrophysical neutrinos from the Seyfert galaxy NGC 1068 suggests the presence of non-thermal protons within a compact "coronal" region close to the central black hole. The acceleration mechanism of these non-thermal 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 non-thermal protons is established in the reconnection region. Motivated by recent three-dimensional 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). The proton spectrum is $dn_p/dE_p\propto E_p^{-1}$ below the break, and $dn_p/dE_p\propto E_p^{-s}$ above the break, with IceCube neutrino observations suggesting $s \simeq 3$. 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.
Comment: Updated discussion, 8 pages, 3 figures, with Appendices
نوع الوثيقة: Working Paper
DOI: 10.3847/2041-8213/ad192b
URL الوصول: http://arxiv.org/abs/2310.18254
رقم الأكسشن: edsarx.2310.18254
قاعدة البيانات: arXiv
الوصف
DOI:10.3847/2041-8213/ad192b