GAMOW-TELLER STRENGTH FROM THE SE-76(N,P)AS-76 REACTION - IMPLICATIONS FOR THE DOUBLE-BETA DECAY OF GE-76

Cross sections have been measured up to 35 MeV excitation for the Se-7 6(n,p)As-76 reaction at five laboratory angles between 0 degrees and 1 5 degrees. The incident neutron energy was 198 MeV. The distribution o f Grunow-Teller (GT) strength at excitation energies less than 10 MeV was deduced by carrying out a multipole decomposition of the data. The GT strength below 6 MeV excitation was found to be less than 0.9 unit s, in qualitative agreement with a quasiparticle random-phase approxim ation calculation. The present results have been compared with data fr om the Ge-76(p,n)As-76 reaction to obtain an estimate of a lower limit for the lifetime of Ge-76 for beta beta decay. The estimate is in qua litative agreement with the measured lifetime.