Abstract
A scintillation spectrometer and a magnetic lens spectrometer have been used to study gamma rays from excited states of at 3.84 and 3.68 Mev, produced in the reactions and . Lines have been measured at 169.5±0.4 kev, 3.844±0.015 Mev, and 3.69±0.02 Mev. The last one was shown to exhibit a Doppler shift, suggesting a lifetime less than 3× second. The 170-kev line was shown to result from a transition between the 3.84- and 3.68-Mev levels, indicating a level energy 3.675±0.015 Mev. Its internal conversion coefficient was found (assuming an isotropic distribution) to be (1.4±0.3)×, consistent with electric dipole radiation. Lack of knowledge of the angular distribution adds to the uncertainty and makes it impossible to rule out magnetic dipole radiation. Relative line intensities showed that the upper level decayed through the 3.68-Mev level with a probability 0.24±0.05. Transitions to the 3.1-Mev level were not detected and were concluded to have intensities less than 3% of the ground-state transitions.
- Received 26 January 1956
DOI:https://doi.org/10.1103/PhysRev.102.802
©1956 American Physical Society