Simulation-Based Optimization of IceCube-Gen2 Modules for Enhanced Sensitivity to Neutrinos from Galactic Core-Collapse Supernovae*

The IceCube Neutrino Observatory is capable of detecting high-energy astrophysical neutrinos as well as bursts of MeV neutrinos from core-collapse supernovae (CCSNe). The IceCube-Gen2 will encompass nearly tenfold the volume of its predecessor, incorporating cutting-edge multi-PMT Digital Optical Modules (mDOMs) and Wavelength-shifting Optical Modules (WOMs) presently undergoing development and testing. The design of the new modules will have a significant impact on the sensitivity of IceCube to supernova neutrinos. To gauge sensitivity and refine sensor design, we devised a high-fidelity simulation in GEANT4, focusing on mDOMs and WOMs, accounting for depth-dependent ice properties enveloping the modules. The simulation allows for the direct injection of signal events, encompassing supernova neutrino flux with varying progenitor masses, as well as background events stemming from the radioactive decay of trace elements. Leveraging the mDOM simulation, we studied local coincidence in detected neutrinos and used "coincidence cuts" to attenuate background events and minimize the false detection rate of galactic CCSNe. Additionally, the WOM simulation yielded promising results by shifting Cherenkov radiation from the UV to the visible range, where the detectors exhibit peak sensitivity. Consequently, we anticipate WOMs to be more sensitive to supernova neutrinos compared to existing detectors in IceCube. These simulations can play a pivotal role in the optimization of neutrino detectors in IceCube-Gen2, enhancing their sensitivity to MeV neutrino bursts from CCSNe.