TheGe70,72(n,p)70,72Ga reactions: Suppression of Gamow-Teller strength nearN=40

The {sup 70,72}Ge({ital n},{ital p}){sup 70,72}Ga reactions have been measured at a beam energy of 200 MeV in order to study the behavior of Gamow-Teller (GT) strength near the {ital N}=40 subshell closure. The GT quenching factor extracted for {sup 70}Ge is consistent with results for {sup 54}Fe and with calculations done on the quasiparticle random-phase-approximation model if they are renormalized by a factor of about 0.6. The quasiparticle random-phase approximation predicts a drastic reduction in concentrated GT strength from {sup 70}Ge to {sup 72}Ge which is also seen in the data. These results are relevant to models of supernovae.