Speaker
Description
The JSNS2 (J-PARC Sterile Neutrino Search at the J-PARC Spallation Neutron Source) experiment searches for neutrino oscillations at a 24m baseline, targeting Δm² of order 1 eV². For short-baseline oscillation analyses, precise control of the reconstructed energy scale and spatial uniformity of the detector response is essential to reduce systematic uncertainties. In this study, we utilize neutron capture on gadolinium (n-Gd), which produces a well-defined gamma-ray cascade of approximately 8 MeV, as a robust standard candle to monitor and correct the detector response. By specifically employing n-Gd events associated with a large amount of cosmogenic fast neutrons, we ensure independent control samples from IBD signals. Using n-Gd capture events, we developed an energy scale correction framework to achieve stable energy reconstruction and improved spatial uniformity across the detector volume. In this presentation, we report the latest energy scale stability and uniformity performance based on the 2026 dataset.