Mechanism of (d, α) reaction: using vector- and tensor-polarized deuterons

Abstract

Abstract Differential cross sections σ, vector- and tensor analyzing powers iT11, T20, T21 and T22 for the reactions 208 Pb ( d , α) 206 Tl ( gs. 0 − ) and 90 Zr ( d , α) 88 Y ( gs . 4 − and first excit 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 208 Pb ( d , α) 206 Tl (0 − )[ 90 Zr ( d , α) 88 Y (4 − and 5 − )] is an angular-momentum mi [matching] transition. Both reactions have been explained in terms of the sequential transfer ( d, t )( t , α) and ( d , 3 He )( 3 He , α) two-step processes in addition to a (d, α) one-step process which includes the α-particle S- and D-state components.