# High-Energy Neutrinos from Blazar Flares and Implications of TXS 0506+056

## TL;DR

This paper investigates the potential of blazars, especially TXS 0506+056, to produce high-energy neutrinos, analyzing IceCube observations and multi-wavelength data to understand their contribution to cosmic neutrino flux.

## Contribution

It introduces a multi-zone model that explains neutrino emission from TXS 0506+056 while satisfying multi-wavelength cascade constraints, advancing understanding of blazar neutrino production.

## Key findings

- Blazars likely contribute significantly to high-energy neutrino flux.
- A multi-zone model can reconcile neutrino observations with electromagnetic constraints.
- TXS 0506+056 is a key source in high-energy neutrino astrophysics.

## Abstract

Motivated by the observation of a $>290$ TeV muon neutrino by IceCube, coincident with a $\sim$6 month-long $\gamma$-ray flare of the blazar TXS 0506+056, and an archival search which revealed $13 \pm 5$ further, lower-energy neutrinos in the direction of the source in 2014-2015, we discuss the likely contribution of blazars to the diffuse high-energy neutrino intensity, the implications for neutrino emission from TXS 0506+056 based on multi-wavelength observations of the source, and a multi-zone model that allows for sufficient neutrino emission so as to reconcile the multi-wavelength cascade constraints with the neutrino emission seen by IceCube in the direction of TXS 0506+056.