Mechanism of (d,α) reaction: 208Pb(d,α)206Tl and 90Zr(d,α)88Y using vector- and tensor-polarized deuterons

Differential cross sections σ, vector- and tensor analyzing powers iT11, T20, T21 and T22 for the reactions 208Pb(d,α)206Tl(gs. 0-) and 90Zr(d,α)88Y(gs. 4- and first excited state 5-) have been measured near Ed = 22 MeV. Since the transition 208Pb(d,α)206Tl(0-) has a special spin- and parity sequence 1++0+ → 0++0-, its transition matrix has only two independent complex elements: the one is spin-state changed and the other spin-state unchanged. Thus the transition matrix has been completely determined in terms of three observables σ, iT11 and T20, i.e., a complete experiment has been carried out. The data for the (d,α) reactions on 208Pb and 90Zr have been analyzed by the method of the first- and second-order finite-range distorted wave Born approximation. The reaction 208Pb(d,α)206Tl(0-)[90Zr(d,α)88Y(4- and 5-)] is an angular-momentum mismatching [matching] transition. Both reactions have been explained in terms of the sequential transfer (d,t)(t,α) and (d,3He)(3He,α) two-step processes in addition to a (d,α) one-step process which includes the α-particle S- and D-state components. (orig.)