Uncovering neutrinos from cosmic ray factories: The Multi Point Source method

We present a novel method for the search of high energy extraterrestrial neutrinos in extended regions. The method is based on the study of the spatial correlations between the events recorded by neutrino telescopes. Extended regions radiating neutrinos may exist in the Galaxy due to the hierarchical clustering of massive stars, the progenitors of all the Galactic accelerators known so far. The neutrino emission associated to such extended regions might be faint and complex due to both the escape of cosmic rays and the intricate distribution of gas in the environment of the accelerators. We have simulated extended neutrino emission over an area of 10°×10°, where the intensity fluctuations across the region are modelled as a Gaussian random field with a given correlation structure. We tested our proposed method over realizations of this intensity field plus a uniform random field representative of the spatial distribution of the atmospheric neutrino background. Our results indicate that the method proposed here can detect significant event patterns that would be missed by standard search methods, mostly focused in the detection of individual hot spots.