Dielectronic recombination in He-like, Li-like and be-like bismuth and KLM resonances

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Journal of Physics: Conference Series

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Dielectronic Recombination in He-like, Li-like and

Be-like Bismuth and KLM Resonances

To cite this article: Ilhan Yavuz et al 2012 J. Phys.: Conf. Ser. 388 062039

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Dielectronic Recombination in He-like, Li-like and Be-like Bismuth

and KLM Resonances

Ilhan Yavuz∗, Ay¸se Yumak∗, Erdi A. Bleda †, and Zikri Altun∗ 1 ∗_{Department of Physics, University of Marmara, 34722, Ziverbey, Istanbul, TURKEY} †_{Department of Mathematic and Computer, AREL University, Tepekent, Istanbul, TURKEY}

SynopsisDR rate coefficients for He-like, Li-like and Be-like Bismuth ions and KLM resonances are calculated using MCBP approximation.

The spectral emission of highly charged ions with few electrons has been used heavily in the diagnostic analysis of astrophysical and labora-tory plasmas. Rate coefficients for dielectronic recombination (DR) process are essential in this respect. We report results from a final state level-resolved DR rate coefficient calculations for the ground and metastable initial levels of He-like, Li-He-like, and Be-like isonuclear ions of Bis-muth. We used the code AUTOSTRUCTURE [1] within the multi configuration Breit-Pauli approximation with kappa-averaged relativistic wave functions. Slater-Type Orbital model po-tential to represent the Coulomb interactions be-tween pairs of electrons is used for the calcu-lations of radial orbitals. The autoionization rates are calculated in the isolated resonance ap-proximation using a distorted-wave approxima-tion where both electron and electron-photon interactions are treated to first order. Both ∆n = 0 and ∆n = 1 core excitations in-volving 1s and 2s subshells were included. The dielectronic capture process to nl Rydberg levels is assumed to take place explicitly with n and l values ranging between 0-6 and 2-25, respec-tively, for ∆n = 0 core excitations. For the case of ∆n = 1 core excitations n values are explic-itly included upto 15. An approximation for the highlevel values of n was used up to n=1000 in ei-ther cases. Calculations embrace a wide range of electron temperature range (105

− 10

11

)K. AU-TOSTRUCTURE produces raw autoionization and radiative rates which are post-processed via ADASDR to obtain the final-state level-resolved and total DR rate coefficients. Maxwellian-averaged total DR rate coefficients are shown in Figure 1 a. Resonances in Fig. 1 b, c and d re-sult from the autoionizations of 1s2l3l′_{, 1s2s2l3l}′_,

and 1s2s2

2l3l′_{configurations associated with the}

∆n = 1 core transitions during the capture of electrons by He-like, Like-like and Be-like

Bis-muth ions, respectively, with l=0-1 and l′_=0-2.

50000 52000 54000 56000 0,0 0,6 1,2 1,8 0,2 0,7 1,2 0,2 0,7 1,2 1,7 51420 51440 51460 51480 51500 0,00 0,05 0,10 0,15 0,20 50900 5100051100 5120051300 51400 0,0 0,1 0,2 50400 50700 51000 0,0 0,2 0,4 0,6 10 4 10 6 10 8 10 10 10 12 10 -18 10 -16 10 -14 10 -12 10 -10 10 -8

Center of Mass Energy (eV) He-like Bi D R R a t e C o e f f i ci e n t s ( 1 0 -1 0 cm 3 sn -1 ) Li-like Bi Be-like Bi (d) (c) (b) (a) R a t e C o e f f i ci e n t ( cm 3 sn -1 ) Temprature (K) He-like Bi Li-like Bi Be-like Bi

Figure 2. Maxwellian-average rate coefficients for He-like, Li-like, and Be-like Bismuth ions(a). (b)-(d) show the resonances resulting from the autoion-zations of the 1s2l3l′_{, 1s2s2l3l}′_{, and 1s2s}2_2l3l′_for

He-like, Li-like, and Be-like Bismuth ions, respec-tively.

References

[1] Badnell, N. R. 1986, J. Phys. B, 19, 3827; Bad-nell, N. R. 1997, J. Phys. B, 30, 1; BadBad-nell, N. R., OMullane, M., Summers, H. P., et al. 2003, Astron. and Astrophys., 406, 1151.

1_E-mail: _{zikalt@marmara.edu.tr}

XXVII International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC 2011) IOP Publishing Journal of Physics: Conference Series 388 (2012) 062039 doi:10.1088/1742-6596/388/6/062039