Speaker
Description
$^{50}$V is one of the high-order forbidden beta decay isotopes of interest in nuclear physics due to its extremely rare decay process. The decays of 50V to the ground states of $^{50}$Ti and $^{50}$Cr are classified as fourfold forbidden decays involving a significant spin change (ΔJ=6).
Notably, the beta decay mode transitioning to 50Ti has never been observed, and its half-life is known only as an upper limit. Based on theoretical calculations using the shell model, the half-life of the beta decay of 50V is estimated to be about 2 $\times$ 10$^{19}$ years, while the latest limit value is reported to be 1.9 $\times$ 10$^{19}$ years (90% C.I.) at the Gran Sasso Underground Laboratory (LNGS).
The Center for Underground Physics (CUP) in Korea has the CAGe (CUP Array of HPGe Detectors), an array of 14-channel HPGe detectors designed for high-sensitivity measurements in rare event physics research. Research on the decay of 50V has been conducted using CAGe, with a purified vanadium metal sample weighing 788 grams which used in 2019 at the LNGS.
Preliminary results from the first run, which involved approximately 100 days of data collection, were recently obtained. The initial results will be reported in this talk.
