[PDF]    http://dx.doi.org/10.3952/lithjphys.54201

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 54, 6779 (2014)


P. Bogdanovich, R. Kisielius, and D. Stonys
Institute of Theoretical Physics and Astronomy, Vilnius University, A. Goštauto 12, LT-01108 Vilnius, Lithuania
E-mail: pavelas.bogdanovicius@tfai.vu.lt

Received 20 December 2013; revised 13 March 2014; accepted 29 May 2014

We describe the computer codes, developed at Vilnius University, for the calculation of electron-impact excitation cross sections, collision strengths, and excitation rates in the plane-wave Born approximation. These codes utilize the multireference atomic wavefunctions which are also adopted to calculate radiative transition parameters of complex many-electron ions. This leads to consistent data sets suitable in plasma modelling codes. Two versions of electron scattering codes are considered in the present work, both of them employing configuration interaction method for inclusion of correlation effects and Breit-Pauli approximation to account for relativistic effects. These versions difer only by one-electron radial orbitals, where the first one employs the nonrelativistic numerical radial orbitals, while the other version uses the quasirelativistic radial orbitals. The accuracy of produced results is assessed by comparing radiative transition and electron-impact excitation data for neutral hydrogen, helium, and lithium atoms as well as highly charged tungsten ions with theoretical and experimental data available from other sources.
electron impact, excitation, many-electron ions
PACS: 31.15.ag, 34.80.Dp, 95.30.Ky


P. Bogdanovičius, R. Kisielius, D. Stonys
Vilniaus universiteto Teorinės fizikos ir astronomijos institutas, Vilnius, Lietuva

Aprašome Vilniaus universiteto Teorinės fizikos ir astronomijos instituto Atomo teorijos skyriuje sukurtas kompiuterines programas, skirtas skaičiuoti atomų ir jonų sužadinimo elektronų smūgiais skerspjūvius, smūgių stiprius ir sužadinimo greičius plokščiųjų bangų pirmajame Borno artinyje. Šios programos naudoja daugiakonfigūracines daugiatermes atomo bangines funkcijas; tos pačios banginės funkcijos yra pritaikomos sudėtingų daugiaelektronių jonų radiacinių šuolių parametrams (šuolių bangų ilgiams, šuolių osciliatorių stipriams, šuolių tikimybėms) skaičiuoti. Tokiu būdu įmanoma gauti patikimus duomenis, tinkamus plazmų modeliavimo programoms.
Šiame darbe tiriame dvi skirtingas elektronų sklaidos programas, tačiau jos abi naudoja konfigūracijų sąveikos metodą koreliaciniams efektams įskaityti bei Breito ir Paulio artinį, leidžiantį įvertinti reliatyvistinius efektus. Šios dvi programos skiriasi tik vienelektronėmis radialiosiomis orbitalėmis; pirmoji programa naudoja nereliatyvistines skaitines radialiąsias orbitales, o antroji – kvazireliatyvistines radialiąsias orbitales. Mūsų duomenų tikslumą įvertiname palygindami juos su kitų autorių neutralių vandenilio, helio ir ličio atomų bei daugiakrūvių volframo jonų radiacinių šuolių ir sužadinimo elektronų smūgiais teoriniais rezultatais bei eksperimentiniais duomenimis.

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