The total cross sections for the reactions ${}_{}{}^7{}_{}{}^{}\mathrm{Li}(p, p^{\prime }){}_{}{}^7{}_{}{}^{}\mathrm{Li}\left(478\mathrm{} \mathrm{keV}\right)$ and ${}_{}{}^7{}_{}{}^{}\mathrm{Li}(p, n){}_{}{}^7{}_{}{}^{}\mathrm{Be}\left(431\mathrm{} \mathrm{keV}\right)$ have been measured for proton energies between 23 and 52 MeV and compared with the predictions of a microscopic model of the reaction. The spin-flip, isospin-flip part of the effective interaction is found to be essentially independent of energy, whereas the pure central part appears to decrease with increasing energy.

• Received 28 August 1967

DOI:https://doi.org/10.1103/PhysRevLett.19.1141