Abstract
The reaction has been studied up to 5-Mev bombarding proton energy with good resolution using targets of high isotopic enrichment. Levels previously unseen in this reaction were found at proton energies of 3.19 Mev ( kev), 3.38 Mev ( kev), 3.63 Mev ( kev), 3.89 Mev ( kev), 4.19 Mev ( kev), 4.24 Mev ( kev), 4.61 Mev ( kev), and 4.93 Mev ( kev). Excitation curves at three angles in the region of 2.9-Mev proton energy show the effect of the previously known ( kev) resonance interfering with a level of opposite parity. Effects of the nearby ( kev) level are not seen, presumably due to the low penetrability of the outgoing -wave neutron. The thresholds for the second and third neutron groups were investigated using a lithium iodide detector. A new threshold, that for production of the third neutron group, was measured to be 4.910±0.008 Mev in agreement with the known energy of the second excited state in .
- Received 25 April 1960
DOI:https://doi.org/10.1103/PhysRev.119.1948
©1960 American Physical Society