FERMI AND GAMOW-TELLER STRENGTH IN CHARGE-EXCHANGE WITH RADIOACTIVE BEAMS

At forward angles, and bombarding energies E > 200 MeV, (p, n) and (n, p) reactions are thought to be directly proportional to the Gamow-Tel ler transition strengths in the nuclei. Assuming that this relationshi p also holds for charge exchange induced by high-energy heavy ions, th is technique would be very useful in studies with radioactive beams. W e show that the determination of Gamow-Teller and Fermi matrix element s from heavy-ion charge-exchange at forward angles is only useful for particular cases. (C) 1997 Elsevier Science B.V.