Electron impact excitation of magnesium and zinc atoms in the relativistic distorted-wave approximation

Abstract

A calculation based on a relativistic distorted-wave approximation has been carried out for the electron impact excitation of the 3

Electron scattering from magnesium at an incident energy of 20 eV

“…The linear polarizations from that study were well reproduced by both the CCC (Fursa and Bray 2001) and RMPS methods. The relativistic distorted-wave (RDW) method of Kaur et al (1997) and the first-order many-body theory (FOMBT) of Meneses et al (1990) also showed substantial agreement with experiment. It might be expected that distorted-wave methods would work well at this energy of almost ten times the excitation threshold.…”

“…The present CCC and RMPS calculations are in excellent agreement with each other Figure 2. Differential cross sections for elastic scattering and excitation of the 3 1 P and 3 3 P states of magnesium at 20 eV: (•) present data; ( ) Brunger et al (1989) (3 1 P), Houghton et al (1994) (3 3 P); (×) Williams and Trajmar (1978) Mitroy and McCarthy (1989); (---) FOMBT (Meneses et al 1990); (----) RDW (Kaur et al 1997).…”

“…Figure 1. The Stokes and charge-cloud shape parameters, P 1 , P 2 , P 3 , γ, P , and the total polarization, P, for the 3 1 P state of magnesium at an incident electron energy of 20 eV as a function of electron scattering angle: (•) present measured data; (•) present P 3 data calculated from the measured P 1 and P 2 values and the sign chosen identical to the measured one; ( ) Brunger et al (1989); (--) present CCC; (-· · -) present RMPS; (-· -) present RM9; (− − − − −−) RDW (Kaur et al 1997); (· · · · · ·) FOMBT (Meneses et al 1990).…”

Electron-photon correlations in electron-impact excitation of alkaline-earth atoms

“…For the L± parameter the agreement between the experiment, present CCC, RDWA [8,9], and DWA [16,14,17], and calculations are very good in the forward scattering region for Mg, Ca, and Sr but not for Ba where large differences between theoretical results are apparent. At intermediate scattering angles the CCC method is in a good agreement with experiment for Mg, Ca, and Ba but for Sr we found a large discrepancy at around 50° with the DWA and RDWA results supporting the experiment.…”

“…1 and 2 for Mg (40 eV), Ca (45eV), Sr (30.3 eV), and Ba (20 eV). The results of the RDWA calculations [8,9] and experimental data indicate that relativistic effects are not important for these transitions, since both find that P + is approximately unity.…”