Speaker
Description
Molybdenum-100 is one of the popular isotopes used to search for double beta decay and to study nuclear matrix elements. The half-lives of the two neutrino double beta decays of Mo-100 to the various excited states of Ru-100 were investigated with two samples of Mo-100-enriched molybdenum trioxide powders. The measurements were performed using an array of fourteen HPGe detectors, CAGe, located in the 700-m-deep Yangyang underground laboratory, Korea. Each detector element has 70% relative efficiency, and the total crystal volume of CAGe is 4093 cm^3. The mass and assay duration of powder #1 was 14.8 kg and 146 days, and powder #2 was 12.0 kg and 170 days, respectively. The half-life of the two neutrino double beta decay to the second excited state was measured to be similar to the previous experiments performed by other groups. On the other hand, the other excited states were found to have higher limits at 90% C.L. than other groups.
