Abstract
The elastic scattering cross sections for and have been measured in the energy ranges 23.5-39 and 25-39 MeV, respectively. These data have been compared with the Mainz total photonuclear absorption cross sections and interpreted in terms of a form factor applied to the gauge term of the Thomson amplitude as well as an E2 amplitude. For the E2 strength found is total, isoscalar plus isovector, energy-weighted sums, and for . All of the data taken at 23.5 MeV, the peak of the giant resonance, where the real part of the scattering amplitude vanishes, have been combined to determine the total photonuclear absorption cross section at that energy, 19.7±0.4 mb. The branching ratio at 23.5 MeV was found to be 0.23±0.07.
NUCLEAR REACTIONS Measured for and , MeV, determined .
- Received 15 March 1983
DOI:https://doi.org/10.1103/PhysRevC.28.8
©1983 American Physical Society