Detecting Thunderstorm‐Related High‐Energy Phenomena in Weak Signals

Abstract Gamma‐ray glows (GRGs) are high‐energy events associated with thunderstorms, characterized by an enhancement of the high‐energy background radiation lasting from a few seconds to several minutes. They are typically detected near their sources by balloons, aircraft, mountain‐based observatories, or at sea level in regions where thunderstorms develop at low altitudes, such as in the western coastal regions of Japan. To investigate these events, a BGO scintillator was installed on the roof of the W‐2 building at the University of Electro‐Communications in Chofu, Tokyo, in the summer of 2023. In February 2024, a weak GRG was detected using a new statistical approach that combines Gaussian convolution with Bayesian inference and Continuous Wavelet Transform. This method demonstrates strong potential for extracting weak signals buried in noise, offering a powerful tool for detecting GRGs of low intensity. Beyond individual detections, it provides a new way to reveal events that would otherwise remain unnoticed due to their low intensity, thereby opening new perspectives for studying the occurrence rate and rarity of GRGs.