C.A. Goulding

Splitting of the Dipole and Spin-Dipole Resonances

Cross sections for the 90,92,94Zr(p,n) reactions were measured at energies of 79.2 and 119.4 MeV. A phenomenological model was developed to describe the variation with bombarding energy of the position of the L=1 peak observed in these and other (p,n) reactions. The model yields the splitting between the giant dipole and giant spin dipole resonances. Values of these splittings are obtained for isotopes of Zr and Sn and for 208Pb.

Qualielastic scattering of pions from 12C and 40,44,48Ca

Measurements have been made of the differential cross section d2σ/dΩdE for π+ scattered from 12C aNd 40,44,48Ca in the energy region corresponding to quasielastic scattering, using the EPICS facility at LAMPF. Data were taken at 180 Mev, 60°, And 290 Mev, 60° and 120°. Corrections were made for muon contamination, using information found on muons seen in π‐p scAttering measurements. A sample of the data is shown in Fig. 1. The rest of the for each of the two angles are very similar in character to this. Within the errors, no simple systematic effects can be seen either in the Ca isotope cross sections or in the π−/π+ ratios. These results are being studied using calculations based on pion scattering from a Fermi gas of nucleons.