Analyzing powers for (p,d) reactions on 208Pb and 142,144Nd exciting neutron-hole states at Ep = 22.0MeV

Abstract

Vector analyzing powers A( θ) and cross sections σ(θ) have been measured for ( p , d) reactions on 208Pb and 142,144Nd using a polarized proton beam of 22.0 MeV and a magnetic spectrograph. Excitations of neutron-hole states of p 1 2 , p 3 2 , f 5 2 , f 7 2 , h 9 2 and i 13 2 have been observed in the 208Pb(p, d) 207Pb( N = 125) reaction, those of f 7 2 and p 3 2 in the 144Nd(p, d) 143Nd( N = 83) reaction and those of d 3 2 , S 1 2 and > h 11 2 in the 142Nd(p, d) 141Nd( N = 81) reaction. Angular distributions of A( θ) and σ( θ) have been measured from 5° to 65° in 5° or 2.5° steps. A good agreement between measured and calculated A( θ) and σ( θ) was obtained for the l = 0,1,2,3 (p,d) transitions employing one-step zero-range distorted-wave Born approximation (DWBA) theory with the adiabatic model proposed by Johnson and Soper. The (p, d) transitions with large angular momentum transfer of l = 5 and 6, however, were not interpreted in terms of the DWBA at forward angles where a large angular momentum mismatch occurred. A strong j-dependence in the analyzing powers has been observed for the pairs of transitions of p 1 2 − p 3 2 and f 5 2 −f 7 2 in the 208Pb( p , d) 207Pb reaction, and has been reproduced well with the DWBA calculations. The analyzing powers for the f 7 2 ( p 3 2 ) transitions of the 208Pb( p , d) 207Pb and 144Nd( p , d) 143Nd reactions were out of phase with each other. The results were explained to be due to the difference in nuclear radii of the optical potentials for protons and deuterons between 208Pb and 144Nd. Spectroscopic factors were extracted and discussed.