Speaker
Description
Ordinary Muon Capture (OMC) provides a unique experimental avenue to probe the β+ type nuclear responses essential for understanding double beta decays (DBDs) and astrophysical neutrino interactions. This study leverages high energy-resolution gamma-ray spectroscopy to meticulously identify transition channels in enriched and natural molybdenum. By utilizing high-purity germanium (HPGe) detectors, we resolve complex spectra to determine precise branching ratios for (µ, xnν), and (µ, xnpν) particle emission channels. These high-resolution datasets enable the identification of ppb-level elemental impurities for extracting the spin states involves during OMC. Within the framework of the Proton Neutron Emission Model (PNEM), the µ capture strength distribution across the Giant Resonance (GR) region (0–70 MeV) were mapped. In this region, nuclear transitions are predominantly driven by low multipole states (0±, 1±, 2±), with only minor contributions originating from higher multipole states (5±, and 6±). These high-resolution observations serves as crucial benchmarks for theoretical pn-QRPA calculations, and aid in understanding nuclear structure deformations relevant to hypothetical 0νββ decay, providing the critical experimental constraints needed to refine theoretical Nuclear Matrix Elements (NMEs).
