IceCube Search for High-Energy Neutrinos Produced in the Precursor Stages of Gamma-ray Bursts
2019 July 22
While gamma-ray bursts (GRBs) were once believed to be a dominant source of astrophysical neutrinos, the lack of any significant correlation between high-energy photons and neutrinos has resulted in stringent limits on their neutrino fluxes. Previous IceCube searches for neutrinos from GRBs have generally focused on the prompt phase of GRBs. However, the higher density during the GRB precursor stage could lead to more hadronic interactions, and therefore be the predominant time of neutrino emission. We present results from an analysis of Fermi-GBM data to identify and characterize individual precursor flashes. Together with an up-to-date catalog of GRBs, we have made our results available via an online tool. An IceCube analysis method to search for neutrinos arriving coincident with GRB precursors has been developed. In this presentation, we compare the sensitivity of this analysis to previous IceCube analyses and discuss the implications in case a significant signal is found.