Abstract
Two measurements have been made which are relevant to the parity of . In one experiment the gamma-ray spectrum from a mixed source of 13.6-sec and 7.4-sec activities was examined with a 3-mm-thick lithium-drifted germanium detector having an experimental linewidth of 13 keV for 6-MeV gamma rays. Based on a calibration from lines due to the 6.132- and 7.116-MeV gamma rays in the decay of , the 6.8-MeV gamma ray in the decay of has an energy of 6.792±0.006 MeV. This is in agreement with the excitation energy of the or upper member of the 6.752-6.804-MeV doublet in . In the other experiment a magnetic pair spectrometer measurement was made on the ground-state and first-excited-state transitions from the 7.99-MeV level as excited in the reaction. It was shown that these transitions are , thereby requiring even parity for the 7.99-MeV state, and that the spin of the state is . Since the beta-ray transitions of to the 6.804- and 7.99-MeV levels of are both known to have allowed values, the parity of is even.
- Received 9 July 1964
DOI:https://doi.org/10.1103/PhysRev.136.B916
©1964 American Physical Society