Dielectronic recombination rate coefficients of carbon-like Kr30+

Abstract

Abstract Dielectronic recombination (DR) rate coefficients for carbon-like Kr30+ have been measured over the collision energy of 0–60 eV using the heavy-ion storage ring CSRe at the Institute of Modern Physics in Lanzhou, China. The present DR spectrum covers the resonances associated with the 2 s 2 2 p 2 [ 3 P 0 ] → 2 s 2 2 p 2 [ 3 P 1 , 2 ] , 2 s 2 p 3 and 2 p 4 ( Δ n = 0 ) core excitations. The corresponding DR resonance energies and strengths have been calculated by using the flexible atomic code (FAC) to understand the measured results. An overall agreement has been obtained between the experiment and theory, except for the data at the collision energies below 7 eV and in 35–38 eV, where the electronic correlation effect is strong. In particular, the resonances from the trielectronic recombination due to 2 s 2 2 p 2 + e − → 2 p 4 [ 1 D 2 ] 6 l have been identified with the help of the FAC calculation. Temperature-dependent plasma recombination rate coefficients were derived from the measured DR rate coefficients for the temperature range 103–107 K and compared with our FAC calculations as well as the previous AUTOSTRUCTURE calculations by Zatsarinny et al (2004 Astron. Astrophys. 417 1173–81). The FAC and AUTOSTRUCTURE calculations are in good agreement with the presently derived plasma rate coefficients. The present work provides the benchmark data for astrophysical and laboratory plasma modeling.