Measurements of Gamow-Teller strength distributions in masses 13 and 15

The differenctial cross section and the transverse spin-flip probability have been measured for the dominant transitions in C13(p,n) 13N and 15N(p,n) 15O at Ep=160 MeV. The Gamow-Teller transition strengths deduced from the data show that the major (1/2)-(3/2)- transitions are strongly quenched relative to the (1/2)-(1/2)- mirror transitions, in strong disagreement with simple shell-model expectations. © 1985 The American Physical Society.