Integral and differential cross section for electron-impact excitation of 12 of the lowest states of argon

Abstract

A semi-relativistic first-order distorted-wave Born theory has been used to calculate differential and integral cross sections for electron-impact excitation of the argon atom to 12 different states in the 3p 5 4s and 3p 5 4p manifolds. The calculations were performed at energies between threshold and 150 eV. Our results show that a single-configuration representation is adequate for these excited states of argon. In general, reasonably good agreement between theory and experiment is found at higher energies for those states which can be excited by a first-order direct transition and mixed results are found for those states which can only be excited by exchange transitions in first order.

Electron-impact excitation of argon: I. The 4s´[½]1, 4p[½]1and 4p´[½]0states

“…Integrated cross sections for the 4p states are presented in table 6, with other available results for comparison. •, present work (error bars indicate only the statistical error); , experiment of Chutjian and Cartwright (1981); --, SRDWBA results of Madison et al (1998); ----, SCGS RDW result of Kaur et al (1998).…”

“…de Jongh (1971) 20-200 Q i Tam and Brion (1973) 30 5-90 Relative DCS McConkey and Donaldson (1973) Q i Lewis et al (1975) 30, 40, 50, 60, 80, 100, 120 15-140 Relative DCS, r Chutjian and Cartwright (1981) 16, 20, 30, 50, 100 5-138 DCS, Q i , Q m Khakoo et al (1992) 30 10-120 DCS Khakoo et al (1994) 30 0-50 Relative DCS, r Tsurubuchi et al (1996) Onset-1000 Q i Chilton et al (1998) Onset-300 Q i Present work 16, 20, 30, 40, 50, 80 5-150 1991) limited their DWBA calculation to the integral cross sections for the 4p, 3d and 5s states. Madison (1987, 1992) have reported DCS results for the 3p 5 4s states in noble gases obtained by using DWBA and including relativistic effects in the distorted-wave Born approximation (RDWBA), respectively.…”

“…The calculation by Zuo et al (1992) applied to the excitation of 3p 5 4s states in heavy noble gases used the completely relativistic distorted wave approximation (CRDWA). Recently, Madison et al (1998) exploited semi-relativistic first-order distorted-wave Born theory (SRDWBA) to calculate DCSs for the lowest 12 argon states. Zeman et al (1998) performed a semi-relativistic R-matrix (SRRM) calculation of the 3p 5 4s states.…”

“…Integral cross section measurements were reported by de Jongh (1971) and by McConkey and Donaldson (1973). Tsurubuchi et al (1996) determined level excitation cross sections by measuring electron-impact emission cross sections using a polarization-free method.…”

Argon 4sand 4pExcited States Atomic Data Applied in ARC-JET Modeling

“…Here also, results from DW and FOMBT are compared with RDW results [17]. More theoretical results [19,[22][23][24] and also experimental results [20,25] are presented. We also show Q-C values obtained following Drawin [12] and Sobelman [26].…”