(HE-3,T) CHARGE-EXCHANGE REACTIONS AT E(HE-3)=450 MEV, THETA=0-DEGREES

Spin-isospin excitations in nuclei have been studied by means of the (He-3,t) reactions at 450 MeV on the targets Be-9, (nat)C, Si-28, Ni-58, Ni-62, Zr-90, Sn-118, Sn-120, 124Sn, and Sm-154. The new spectrometer ''Grand Raiden'' was employed for the (He-3,t) study for the first time. Observed (He-3,t) spectra at 0-degrees show remarkable similarity with those from the (p,n) results at intermediate energies, suggesting a simple direct reaction mechanism for the (He-3,t) reaction at 450 MeV. The Gamow-Teller (GT) resonances and the spin-flip DELTAL = 1 resonances are excited very strongly. A fine structure of the GT resonances in medium-heavy nuclei is observed with an energy resolution of 210 keV. It is demonstrated that the (He-3,t) reaction at 450 MeV is a powerful tool to study the spin-isospin excitations in nuclei