The 12C(6Li, d)160 reaction has been studied at E(~Li)= 90.2 MeV with a magnetic spectrometer. Spectra up to E x ~ 30 MeV in 160 have been obtained and decay line widths, F~ .... have been extracted for broad levels. Known a-cluster states (J" = 2 +, E x = 6.9 MeV; J~= 4 +, E x = 10.35 MeV) are preferentially populated and exhibit sharply forward peaked angular distributions in contrast with (eLi, d) data obtained at lower bombarding energies. These features are well reproduced by reaction calculations assuming direct alpha-particle transfer provided one utilizes realistic optical model, target, and projectile wave functions. Alpha spectroscopic factors and reduced alpha widths have been extracted for levels E~ < 12 MeV including J~ = 1-levels of astrophysical interest. The results are compared with other recent measurements and theoretical calculations. There is generally at least qualitative agreement (within × 2) between the various experiments and theories. The analysis indicates a non-negligible alpha width for the J" = 1 -level at E, = 7.1 MeV in 160 (which determines the ~ 2C ~ 160 stellar helium burning rate) with 0.3 < 0~ 2 (7.1 MeV)/0~ (9.6 MeV) < 0.6 and 0.1 < 02 (7.1 MeV)/0~ (6.9 MeV) < 0.4. E NUCLEAR REACTION IzC(6Li, d), E = 90.2 MeV: measured a(Ed, 0~). 160 deduced e-cluster states, a-reduced widths, S~, resonances, F. Optical model, direct e-transfer mechanism, realistic target, projectile wave functions. Magnetic spectrometer.

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Various light-and heavy-ion reactions, 20 < E i 100 MeV, have been used to study the reaction dependence of a-decay widths for *Be*(2+, 2.9 MeV) and '60*(1-, 9.6 MeV). Although slight differences (< 20 %) are found for the observed line shapes (F), the resonance widths inferred (F,) are self-consistent and indicate little if any reaction dependence (i 10 %). Near a decay threshold one may expect F < FR by 20 % or more, however, and thus care must be taken in comparing decay widths inferred from nuclear reactions with those from scattering resonances. Reduced formal a-decay widths of y: = 68Ok 100 keV (s = 4.8 fm) and 7: = 350+50 keV (S = 5.4 fm), corresponding to 19: = 0.50 and 6: = 0.49 are deduced for sBe*(2+, 2.9 MeV) and 16G*(]-, 9.6 MeV) using the nuclear-reaction Fa values and a particular set of a-nucleus potentials.

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