Elastic and inelastic scattering of polarized protons from the isotopes 104, 106, 108, 110Pd

Abstract

Vector analyzing powers A( θ) and differential cross sections σ(θ) have been measured for (p, p) scattering from the four Pd isotopes 140, 106, 108, 110Pd and for (p, p') scattering exciting the first 2 + (2 1 +) and the first 3 − (3 1 −) states of each of the Pd isotopes by using a 22.0 MeV polarized proton beam. Angular distributions of A( θ) and σ(θ) have been measured from 20° to 150° in 5° or 2.5° steps using a magnetic spectrograph. The analysis was made with the optical potential model, with the first-order distorted-wave Born approximation (DWBA) and with coupled channel (CC) calculations. A macroscopic description of the collective quadrupole (octupole) surface vibration of medium-heavy mass nuclei explains very well both the analyzing powers and cross sections for the inelastic scattering of protons exciting the 2 1 + (3 1 −) states of the four Pd isotopes. The quadrupole spin-orbit deformation plays an essential role in reproducing the observed 2 1 + analyzing powers, while the octupole spin-orbit deformation yields little effect on the 3 1 − analyzing powers. The effect of the channel coupling between the 0 g + and the 2 1 + (the 0 g + and the 3 1 −) states is not so large that the experimental data for the 2 1 + (3 1 −) states of the four Pd isotopes can be interpreted essentially with the first-order DWBA calculations. The extracted deformation parameters β 2 (β 3) increase (decrease) systematically with increasing of the mass number from 104Pd to 110Pd.