Franciska Sprok, Edit Fenyvesi, Gabor Gyula Kiss, Denes Molnar, Gergely Gabor Barnafoldi (2025.10.01 - 2025.12.31)

Abstract: The consistency of nuclear decay rates can be investigated through long-duration precision measurements. Whether long-term or short-term fluctuations occur remains an open question. Our project aims to identify the presence of such modulations, with particular focus on annual variations. We measure the decay rate of a 137-Cs source at the Jánossy Underground Research Laboratory using a High-Purity Germanium (HPGe) detector. Gamma-ray spectroscopy is employed to analyze the source, collecting hourly counts over several months to allow identification of both short-term and long-term deviations in the decay rate. Within this project we analyze the huge amount of collected data using massively parallel computational techniques.