High Energy Neutrinos from the Tidal Disruption of Stars

TL;DR

This paper investigates how tidal disruption events (TDEs) involving supermassive black holes could produce high-energy neutrinos detectable by IceCube, suggesting TDEs might explain most observed neutrino fluxes.

Contribution

It provides the first detailed analytical and numerical estimates of the neutrino flux from TDEs, considering their redshift and black hole mass dependence, and explores their potential to account for IceCube observations.

Findings

TDEs could produce up to 10% of IceCube's neutrino flux at 1 PeV.

Adjusting jet Lorentz factors increases TDE contribution to neutrino flux.

A flavor transition signature could indicate TDE origins of high-energy neutrinos.

Abstract

We study the production of high energy neutrinos in jets from the tidal disruption of stars by supermassive black holes. The diffuse neutrino flux expected from these tidal disruption events (TDEs) is calculated both analytically and numerically, taking account the dependence of the rate of TDEs on the redshift and black hole mass. We find that ~10% of the observed diffuse flux at IceCube at an energy of about 1 PeV can come from TDEs if the characteristics of known jetted tidal disruption events are assumed to apply to the whole population of these sources. If, however, plausible scalings of the jet Lorentz factor or variability timescale with the black hole mass are taken into account, the contribution of the lowest mass black holes to the neutrino flux is enhanced. In this case, TDEs can account for most of the neutrino flux detected at IceCube, describing both the neutrino flux normalization and spectral shape with moderate baryonic loadings. While the uncertainties on our assumptions are large, a possible signature of TDEs as the origin of the IceCube signal is the transition of the flux flavor composition from a pion beam to a muon damped source at the highest energies, which will also result in a suppression of Glashow resonance events.