34P(7Li,7Be+γ) reaction at 100A MeV in inverse kinematics.

We report on the first successful extraction of a β + Gamow-Teller strength distribution from a radioactive isotope in an intermediate-energy charge-exchange experiment in inverse kinematics. The ( 7 Li, 7 Be + γ(429 keV)) reaction at 100A MeV was used to measure Gamow-Teller transition strengths from 34 P to states in 34 Si. The results show that little mixing occurs between sd and pf shell configurations for the low-lying 0 + and 2 + states even though 34 Si neighbors the island of inversion and low-lying 2ħω intruder states exist. Shell-model calculations in the sdpf model space are consistent with these findings.