Time-dependent search of neutrino emission from bright gamma-ray flaring blazars with the ANTARES telescope

Abstract

The ANTARES telescope is well suited for detecting astrophysical transient neutrino sources as it can observe with high duty cycle an instantaneous field of view of 2$\pi$ sr. The background due to atmospheric muons and neutrinos can be drastically reduced, and the point-source sensitivity improved, by selecting a narrow time window around possible neutrino production periods. Blazars, radio-loud active galactic nuclei with their jets pointing almost directly towards the observer, are particularly attractive potential neutrino point sources, since they are among the most likely sources of the very high-energy cosmic rays. Neutrinos and gamma rays may be produced in hadronic interactions with the surrounding medium. Blazars generally show high time variability in their light curves at different wavelengths and on various time scales. Using ANTARES data a time-dependent analysis has been carried out searching for neutrino events from a selection of flaring gamma-ray blazars previously observed by the FERMI/LAT experiment and by TeV imaging Cherenkov telescopes. The results of these searches will be presented. If no signal will be discovered upper limits on neutrino fluxes, their comparisons with the published gamma-ray spectral energy distribution and with prediction from astrophysical models will also be reported.