Department of Physics and Astronomy: Publications and Other Research
Date of this Version
July 1981
Abstract
Relativistic Dirac-Fock calculations are presented for the photoelectron angular distribution asymmetry parameter β corresponding to 4d-subshell photoionization in Cd and for the linear polarization PL of the subsequent fluorescence radiation, for photon energies less than 185 eV. Near threshold, our results for β lie lower than previous relativistic Dirac-Slater and nonrelativistic many-body-perturbation-theory (MBPT) calculations. The agreement with very recent measurements by Heinzmann and Schönhense is very good. Our calculations show that PL (2D5/2→2P3/2)=-0.059 and -0.058 at incident photon energies hν=40.2 and 45.6 eV, respectively. These results lie above the nonrelativistic independent-electron theory absolute maximum of -0.061 for PL, but the agreement with recent measurements lying above this maximum is still not very good. Except for this peaking of PL (2D5/2→2P3/2) above the nonrelativistic theory maximum for 40.2≤hν≤45.6 eV, our results at other energies are in general agreement with the nonrelativistic MBPT calculations of Carter and Kelly. We also find that PL (2D3/2→2P3/2)=+ 0.134 at hν=21.2 eV, in excellent agreement with the experimental value of + 0.12±0.04 of Caldwell and Zare.
Comments
Published by American Physical Society. Phys. Rev. A 24, 301 (1981). http://pra.aps.org. Copyright © 1981 American Physical Society. Permission to use.