David K. McDaniels

The decay of 56Ni and 57Ni

Abstract The energies and relative intensities of the gamma radiations following the decays of 56Ni to 56Co and 57Ni to 57Co have been measured using a 3 mm depletion-depth lithium-drifted germanium detector. Gamma rays of the following energies were observed in 56Co (relative intensities in parentheses): 0.1583 (96.1), 0.2696 (38.4), 0.4807 (39.8), 0.7506 (52.2) and 1.5625 (12.3) MeV. Gamma rays populating the levels at 1.008 and 1.105 MeV were not observed. For 57Co the following gamma rays were observed: 0.1272 (12.3), 1.3781 (82.2), 1.7577 (5.7), and 1.9202 (12.1) MeV. No evidence was found for a level at 1.59 MeV. The level schemes are compared with simple shell-model calculations.

An investigation of the levels of 131Xe

Abstract The gamma-ray spectrum from the decay of 131I has been re-investigated using a 3 mm depletion depth lithium-drifted germanium detector. Gamma rays of the following energies and relative intensities were observed in 131Xe: 80.166(1.0), 177.02(0.101), 284.31(2.394), 325.86 (0.090), 364.47(32.28), 502.75(0.146), 636.30(2.931) and 722.92(0.663) keV. A directional correlation measurement of the 80.166–284.31 keV cascade has been performed using a lithium-drifted germanium detector coupled with a gain stabilized NaI(Tl) spectrometer and the spin of the first excited state is shown to be 1 2 .