2020/11/19 by A. D. MacLean, A. T. Laffoley, C. E. Svensson +54
Medicine · Physics and Astronomy · #Atomic physics #Branching fraction #Condensed matter physics #Fermi Gamma-ray Space Telescope #Nuclear Physics and Applications #Nuclear physics #Nuclear physics research studies #Particle physics #Physics #Quantum mechanics #Radiation Therapy and Dosimetry #Spins #nucl-ex
paper · pdf · doi:10.1103/physrevc.102.054325
published as Phys. Rev. C 102, 054325 (2020) · A text label in Figure 12 has been corrected compared to the original submission
openalex publication_date 2020/11/19 · arxiv created 2020/11/20 · arxiv updated 2020/11/23 · openalex created_date 2020/11/23 · openalex updated_date 2026/08/05
A high-precision branching ratio measurement for the superallowed Fermi \ensuremathβ+ emitter 62Ga was performed with the Gamma-Ray Infrastructure for Fundamental Investigations of Nuclei (GRIFFIN) spectrometer at the Isotope Separator and Accelerator (ISAC) radioactive ion beam facility at TRIUMF. The high efficiency of the GRIFFIN spectrometer allowed 63 \ensuremathγ-ray transitions, with intensities down to \ensuremath≈1 part per million (ppm) per 62Ga\phantom\rule4pt0ex\ensuremathβ+ decay, to be placed in the level scheme of the daughter nucleus 62Zn, establishing the superallowed \ensuremathβ branching ratio for 62Ga decay to be 99.8577_\ensuremath-0.0029+0.0023%, a factor of 4 more precise than the previous world average. For several cascades, \ensuremathγ\text\ensuremath-\ensuremathγ angular correlation measurements were performed to assign spins and/or determine the mixing ratios of transitions. In particular, the spin of the 2.342 MeV excited state in the daughter nucleus 62Zn was definitively assigned as J=0. This assignment resolves a discrepancy between previous measurements and has important implications for the isospin symmetry breaking correction, \ensuremathδC1, in 62Ga superallowed Fermi \ensuremathβ decay.