IceCube: Multiwavelength search for neutrinos from transient point sources

In this paper we discuss the strategy developed in order to associate neutrinos with their cosmic sources using historical light curves. Periods of very intense photon activity are selected through a novel analysis approach. The statistical method called Maximum Likelihood Blocks is applied for the .rst time on light curves of high frequency blazars. In order to avoid any possible bias in the selection of periods with intense photon activity, the arrival time and incoming direction of the neutrinos are kept blinded. Following the approach here reported, neutrino fluxes below the atmospheric neutrino background level can become accessible. We report as well on a .rst step to establish a target-of-opportunity program based on neutrinos detected in IceCube which are used as alerting messenger particles.