Multi-epoch leptohadronic modeling of neutrino source candidate blazar PKS 0735+178

TL;DR

This paper models the multi-epoch spectral energy distributions of blazar PKS 0735+178 to understand neutrino production mechanisms, revealing that current data cannot definitively predict neutrino flux but suggest potential neutrino event rates during flares.

Contribution

It introduces a multi-epoch leptohadronic modeling approach for PKS 0735+178, exploring parameter degeneracies and their effects on neutrino flux predictions.

Findings

Multi-wavelength data are insufficient to unambiguously predict neutrino spectra.

A scenario with maximal neutrino flux suggests about 0.2 neutrino events during a 50-day flare.

Parameter degeneracy significantly impacts neutrino flux predictions.

Abstract

The origin of the astrophysical neutrino flux discovered by IceCube remains largely unknown. Several individual neutrino source candidates were observed. Among them is the gamma-ray flaring blazar TXS 0506+056. A similar coincidence of a high-energy neutrino and a gamma-ray flare was found in blazar PKS 0735+178. By modeling the spectral energy distributions of PKS 0735+178, we expect to investigate the physical conditions for neutrino production during different stages of the source activity. We analyze the multi-wavelength data during the selected periods of time. Using numerical simulations of radiation processes in the source, we study the parameter space of one-zone leptonic and leptohadronic models and find the best-fit solutions that explain the observed photon fluxes. We show the impact of model parameter degeneracy on the prediction of the neutrino spectra. We show that the available mutli-wavelength data are not sufficient to predict the neutrino spectrum unambiguously. Still, under the condition of maximal neutrino flux, we propose a scenario in which 0.2 neutrino events are produced during the 50 days flare.