BEXCO - Room F(201/202/203/204)
[NU141] Searching for Arbitrary Low-Energy Neutrino Transients with IceCube
The IceCube Neutrino Observatory, located in the deep ice at the South Pole, is designed to observe neutrinos above 1 TeV. However, its scaler system is highly sensitive to low-energy neutrinos from a Galactic Core Collapse supernova (CCSN). SNDAQ, an online trigger system designed to observe CCSNe neutrino bursts in real time, is running in the detector with 99% uptime. In its current implementation, the time windows used by the SNDAQ trigger are tuned to typical supernova simulations and SN1987A. However, no galactic supernova have been observed with high neutrino statistics so far, and many simulations do not produce an actual explosion. Therefore, it is wise to define a trigger that is not biased by simulations. To improve the sensitivity of the trigger to a much wider range of models, as well as unusual hadronic physics or physics beyond the Standard Model, we have implemented a time-domain search using the Bayesian Blocks algorithm. This technique allows the data themselves to determine the natural timescale of excess counts above background. The Bayesian Blocks window makes the SNDAQ trigger more robust to uncertainties in CCSN neutrino emission models. In addition, it also allows for general sub-threshold transient searches using the scaler system. We describe the implementation and performance of the Bayesian Blocks trigger and discuss improvements in the sensitivity of IceCube to supernovae in the Galaxy and its nearest satellites.