[PDF]    http://dx.doi.org/10.3952/lithjphys.45514

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 45, 347–352 (2005)


INFLUENCE OF THE TWO-ELECTRON TRANSITIONS ON THE RADIATIVE LIFETIMES OF EXCITED LEVELS IN Be ISOELECTRONIC SEQUENCE
P. Bogdanovich and R. Karpuškienė
Institute of Theoretical Physics and Astronomy of Vilnius University, A. Goštauto 12, LT-01108 Vilnius, Lithuania
E-mail: karra@itpa.lt

Received 19 October 2005

The ions of beryllium isoelectronic sequence (6 ≤ Z ≤ 30) are investigated using configuration interaction on the basis of transformed radial orbitals with a variable parameter. The energy spectra and radiative lifetimes of the levels of configurations 2s2, 2s2p, 2p2, 2s3l, and 2p3l are obtained. The aim of the present work is the investigation of the influence of the two-electron transitions. It is shown that the two-electron transitions are decisive for the lifetimes of a few excited levels. The dependence of this influence on Z is discussed.
Keywords: beryllium isoelectronic sequence, radiative lifetimes, two-electron transitions
PACS: 31.15.Ar, 31.25.Eb, 31.25.Jf


DVIELEKTRONIŲ ŠUOLIŲ ĮTAKA BERILIO IZOELEKTRONINĖS SEKOS JONŲ SUŽADINTŲ LYGMENŲ GYVAVIMO TRUKMĖMS
P. Bogdanovičius, R. Karpuškienė
VU Teorinės fizikos ir astronomijos institutas, Vilnius, Lietuva

Naudojant konfigūracijų superpozicijos metodą, transformuotų radialiųjų orbitalių su varijuojamu parametru bazėje ištirti berilio izoelektroninės sekos jonai (6 ≤ Z ≤ 30), gauti konfigūracijų 2s2, 2s2p, 2p2, 2s3l ir 2p3l energijos spektrai ir lygmenų gyvavimo trukmės. Išnagrinėta dvielektronių šuolių įtakos priklausomybė nuo Z. Gauti rezultatai parodė, kad stipriai jonizuotiems atomams konfigūracijos 2s3p lygmenų gyvavimo trukmėms reikšmingiausi yra ne įprasti vienelektroniai šuoliai į konfigūraciją 2s3s. Lygmenų 2s3p 3P0,2 gyvavimo trukmes lemia dvielektroniai šuoliai į konfigūraciją 2p2, o lygmenų 3P1 ir 1P1 – vienelektroniai šuoliai į pagrindinę konfigūraciją 2s2.


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