INTRODUCTION: Neutrinos are elusive, low-energy subatomic particles mostly produced in solar fusion. Because they have minimal mass and no electric charge, they rarely interact with matter, often necessitating large underground detectors to reduce backgrounds and detect their infrequent signals.

PURPOSE: This research aims to develop and test a novel detector capable of distinguishing neutrino interactions in high-background environments, such as those found in space or near nuclear reactors.

METHODS: We use the MARLEY simulation framework to estimate neutrino interactions on 71Ga and to characterize the particles emitted. These results are then fed into Geant4, which models realistic particle interactions within prospective detector geometries. By refining the geometry and materials, we optimize the detector for neutrino detection while rejecting uncorrelated backgrounds. To validate the simulations, we constrain them with experimental data from small, prototype GAGG (Gadolinium Aluminum Gallium Garnet) detector segments tested with various radioactive sources in our laboratory.

RESULTS: MARLEY predicts that half of the relevant neutrino signals feature a time-delayed signature of approximately 100 ns, while the remaining half can be reliably detected only if there is a clear spatial separation between particles. These findings indicate that a highly segmented detector with optically isolated volumes less than 10 mm in size is optimal. Tests with prototype GAGG segments yielded a 3.61 ± 0.07% energy resolution at 137Cs and confirmed reliable detection of 57Co double-pulse decays in the 80–1,150 ns range.

CONCLUSION: In summary, our preliminary results demonstrate that a finely segmented, GAGG-based detector design can effectively identify low-energy neutrino signals amidst complex backgrounds. Continued refinement of the geometry, materials, and data analysis techniques will further enhance detection efficiency and resolution, advancing our capabilities in low-energy neutrino physics.