Search for neutrino emission from blazar <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mi>γ</a:mi> </a:math> -ray flares accounting for possible neutrino time delays

We report the results of the search for the high-energy neutrino emission associated with blazar flares, accounting for a possible lag of neutrinos with respect to the electromagnetic emission, either due to the slowness of the proton energy losses in p γ collisions and/or proton acceleration. We perform two tests, cross-matching neutrinos with energies E ν ≳ 100 TeV from the public catalogue of neutrino alerts IceCat-1 with active galactic nuclei from two source samples based on 1) the MOJAVE database and 2) the CGRaBS catalogue, and utilising Fermi-LAT light curves from the public light curve repository. We scan over a wide range of values of the jet-frame time delay t d e l a y ′ between the neutrino arrival and the time of the prior major γ -ray flare and find a pre-trial ∼ 2 σ correlation at t d e l a y ′ ∼ 10 3 d, which is consistent ( p p o s t − t r i a l ∼ 0.1 ) with expectations under the null hypothesis after trial correction.