Spectra up to 25 MeV excitation in`60 have been obtained from`ZC(6Li, d) at 42 MeV bombarding energy. Angular distributions have been measured for ten states, including two J* = 1-states of astrophysical interest, and appear to be mostly direct x-transfer. In addition, data for`60(6Lî, d)2°Ne(g.s .) and~°Ne "(2 +) have been obtained. Excitation energies and widths have been extracted for states in '60, including several states at E, > 15 MeV. Alpha spectroscopic factors, S and reduced a-widths, ya and 0; have been deduced for levels in '60 and a°Ne and compared with theoretical predictions. The J`= 1-levels in '60 at 7.12 and 9.6 MeV excitation appear to have comparable S, and y; values, viz. y; (7 .12 MeV)/yâ (9 .6 MeV) = 0 .6±ô :i. Both states have apparent Sa and 0; values smaller than that for the J`= 2+ "a-cluster" stateat 6.9 MeV however. Furthermore, the observed line shape for the J`= 1-, 9.6 MeV level indicates l'~.~. = 400±50 keV, which is substantially less than the accepted width for this level (r~.m. = SIOt60 keV). The possible implications of these results for stellar helium burning cal-culat%ns are discussed. NUCLEAR REACTIONS 'ZC(6Li, d)`60,`60(6 Li,d)z°Ne, E = 42.1 MeV ; measured Q(Ee, 0). '60 and z°N e deduced x-spectroscopic factors and reduced a-widths. Magnetic spectrometer .

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Charge-exchange reactions are an important tool for determining weak-interaction rates. They provide stringent tests for nuclear structure models necessary for modeling astrophysical environments such as neutron stars and core-collapse supernovae. In anticipation of (t, 3 He) experiments at 115 MeV/nucleon on nuclei of relevance (A∼ 40 − 120) in the late evolution of stars, it is shown via a study of the 26 Mg(t, 3 He) reaction that this probe is an accurate tool for extracting Gamow-Teller transition strengths. To do so, the data are complemented by results from the 26 Mg( 3 He,t) reaction at 140 MeV/nucleon which allows for a comparison of T=2 analog states excited via the mirror reactions. Extracted Gamow-Teller strengths from 26 Mg(t, 3 He) and 26 Mg( 3 He,t) are compared with those from 26 Mg(d, 2 He) and 26 Mg(p,n) studies, respectively. A good correspondence is found, indicating probe-independence of the strength extraction. Furthermore, we test shell-model calculations using the new USD-05B interaction in the sd-model space and show that it reproduces the experimental Gamow-Teller strength distributions well. A second goal of this work is to improve the understanding of the (t, 3 He) and ( 3 He,t) reaction mechanisms at intermediate energies since detailed studies are scarce. The Distorted-Wave Born Approximation is employed, taking into account the composite structures of the 3 He and triton particles. The reaction model provides the means to explain systematic uncertainties at the 10-20% level in the extraction of Gamow-Teller strengths as being due to interference between Gamow-Teller ∆L = 0, ∆S = 1 and ∆L = 2, ∆S = 1 amplitudes that both contribute to transitions from 0 + to 1 + states.