Coupled Time-Dependent Proton Acceleration and Leptonic-Hadronic Radiation in Turbulent Supermassive Black Hole Coronae

TL;DR

This paper introduces a time-dependent numerical framework that models proton acceleration and multi-messenger radiation in turbulent black hole coronae, successfully reproducing observed neutrino spectra and exploring transient phenomena.

Contribution

It presents a novel coupled model of particle acceleration and radiation that accounts for transient and steady states in black hole coronae, advancing multi-messenger astrophysics.

Findings

Reproduces IceCube neutrino spectrum for NGC 1068

Shows cascade feedback affects proton cooling and acceleration

Predicts delayed multi-wavelength emissions in transient coronae

Abstract

Turbulent coronae of supermassive black holes can accelerate non-thermal particles to high energies and produce observable radiation, but capturing this process is challenging due to comparable timescales of acceleration, cooling, and the development of cascades. We present a time-dependent numerical framework that self-consistently couples proton acceleration--modeled by the Fokker-Planck equation--with leptonic-hadronic radiation. For the neutrino-emitting Seyfert galaxy NGC 1068, we reproduce the neutrino spectrum observed by IceCube, while satisfying gamma-ray constraints. We also consider a transient corona scenario, potentially emerging in tidal disruption events like AT 2019dsg, and show that cascade feedback on proton cooling can impact proton acceleration and radiation processes in weaker coronae, producing delayed optical/ultraviolet, X-ray, and neutrino emissions of $\mathcal O(100~\rm d)$. This flexible tool efficiently models multi-messenger signals from both steady and transient astrophysical sources, providing insights in combining particle acceleration and radiation mechanisms.