Evaluating the Potential for HNL Searches in the IceCube Upgrade

According to the Standard Model, neutrinos should be massless, but due to their oscillations between flavor states, neutrinos have a non-zero mass. The origin of neutrino masses can potentially be explained by the existence of Heavy Neutral Leptons (HNLs), which interact with the mass states of neutrinos through the "see-saw" mechanism. Neutrino telescopes can leverage atmospheric neutrino oscillations to search for Gev-scale HNLs coupled to tau-flavored neutrinos. However, initial HNL searches using the IceCube DeepCore detector were limited by the relatively high energy threshold.This talk presents preliminary sensitivity estimates for an HNL search with the IceCube Upgrade, a planned improvement of the current detectors. The Upgrade will have an energy threshold in the single-GeV regime, potentially enabling a search for low-energy coincident cascades from HNL interactions. This talk presents a simulation-based comparison of the detector response to HNL interactions between DeepCore and the Upgrade. This will form the basis for an Upgrade search using more developed reconstruction methods.