SUB-COULOMB TRANSFER-REACTIONS ON PB-208 WITH CARBON AND OXYGEN PROJECTILES

Single-neutron transfers induced by 12, 13C and 16, 17, 18O projectiles on 208Pb and the 12C(17O, 16O)13C reaction have been studied at energies close to the Coulomb barrier. These processes are well described by the distorted-wave Born approximation. Coupled-channels effects are found to be small. Normalization factors have been determined for all projectile and target transitions, and also for the triton-deuteron overlap by comparison with previous measurements of the 208Pb(d, t)207Pb reaction. The root-mean-square (rms) radii of single-particle neutron wave functions in 208Pb and 209Pb were calculated using known spectroscopic factors. The distribution of the point neutron excess density in the surface region of 208Pb has been derived and its rms radius determined to be 5.93 ± 0.13 fm with a local potential model. This is in good agreement with theoretical predictions, but is considerably larger than estimates based on Coulomb energy differences. The phenomena of core polarisation by the odd particle or hole outside 208Pb is discussed using the single-particle orbitals determined in this work. © 1979.