Abstract
Measurements of the () reaction on , , , and have been made for 70-MeV pions. A magnetic spectrometer was used to momentum analyze the pion beam while thick Nal(T1) detectors were used to determine the proton energy. The experimental resolution was 3 MeV. Data from the and targets were taken around a laboratory scattering angle of 25°. The number of () events from these nuclei was not significantly greater than background contributions, and therefore upper limits on the corss section are presented. Data from the reaction were obtained at proton emission angles of 20 and 32° (lab), while for , measurements were made over the angular range from 33 to 90°. Our experimental cross section for the reaction, obtained by integrating over excitation energies from 0 to 8 MeV, did not agree well with existing theoretical predictions. Results from the reaction indicated excitation of the state of . The cross section for this reaction decreased rapidly for emission angles less than 60°, while at larger angles the cross section was constant within the measured range.
[NUCLEAR REACTIONS , , , , MeV, measured .]
- Received 22 August 1973
DOI:https://doi.org/10.1103/PhysRevC.9.501
©1974 American Physical Society