The Neutrino Contribution of Gamma-Ray Flares from Fermi Bright Blazars

Discussion timeslot (ZOOM-Meeting): 12. July 2021 - 18:00
ZOOM-Meeting URL: https://desy.zoom.us/j/91896950007
ZOOM-Meeting ID: 91896950007
ZOOM-Meeting Passcode: ICRC2021
Corresponding Session: https://icrc2021-venue.desy.de/channel/25-Blazars-AGN-MM/61
Live-Stream URL: https://icrc2021-venue.desy.de/livestream/Discussion-06/7

Abstract:
'High-energy neutrinos are expected to be produced during gamma-ray flares of blazars throughxa0the interaction of high-energy cosmic rays in the jet with photons. As a matter of fact, axa0high-energy neutrino event, IC-170922A, was detected at the time of a gamma-ray flare from blazar TXSxa00506+056 at the level of 3 sigma significance. In this work, we present a statistical study of blazar gamma-rayxa0 flares aiming to constrain their contribution to the blazar neutrino output. We selected 145 gamma-ray bright blazars listed in the Fermi Large Area Telescope (LAT) monitored list and constructed their weekly binned light curves. Using a Bayesian Blocks algorithm to the light curves, we determined the fraction of time spent in the flaring state (flare duty cycle) and the fraction of energyxa0released during each flare. Furthermore, we estimated the neutrino energy flux of each gamma-ray flare by using the general scaling relation $L_nu propto (L_gamma)^gamma$, $gamma=1.5-2$, normalized to the quiescent X-ray flux of each blazar. Comparison of the estimated neutrino energy flux with the declination-dependent IceCubexa0sensitivity enables us to constrain the standard neutrino emission models of gamma-ray flares. We also provide the upper-limit contribution of flares of gamma-ray bright blazars to the isotropic diffuse neutrino flux.'

Authors: Kenji Yoshida | Maria Petropoulou Petropoulou | Kohta Murase | Foteini Oikonomou
Indico-ID: 1062
Proceeding URL: https://pos.sissa.it/395/969