Partial and Total Dielectronic Recombination Rate Coefficients for W${}^{55+}$ to W${}^{38+}$

Abstract

Dielectronic recombination (DR) is the dominant mode of recombination in magnetically confined fusion plasmas for intermediate to low-charged ions of W. Complete, final-state resolved partial isonuclear W DR rate coefficient data is required for detailed collisional-radiative modelling for such plasmas in preparation for the upcoming fusion experiment ITER. To realize this requirement, we continue {\it The Tungsten Project} by presenting our calculations for tungsten ions W${}^{55+}$ to W${}^{38+}$. As per our prior calculations for W${}^{73+}$ to W${}^{56+}$, we use the collision package {\sc autostructure} to calculate partial and total DR rate coefficients for all relevant core-excitations in intermediate coupling (IC) and configuration average (CA) using $\kappa$-averaged relativistic wavefunctions. Radiative recombination (RR) rate coefficients are also calculated for the purpose of evaluating ionization fractions. Comparison of our DR rate coefficients for W${}^{46+}$ with other authors yields agreement to within 7-19\% at peak abundance verifying the reliability of our method. Comparison of partial DR rate coefficients calculated in IC and CA yield differences of a factor $\sim 2$ at peak abundance temperature, highlighting the importance of relativistic configuration mixing. Large differences are observed between ionization fractions calculated using our recombination rate coefficient data and that of Pütterich~\etal [Plasma Phys. and Control. Fusion 50 085016, (2008)]. These differences are attributed to deficiencies in the average-atom method used by the former to calculate their data.

Accepted for publication in Journal of Physics B. Manuscript contains 21 pages, 30 figures, and 7 tables

References in corpus (2)

• Recombination of W18+ ions with electrons: Absolute rate coefficients from a storage-ring experiment and from theoretical calculations
• Partial and Total Dielectronic Recombination rate coefficients for W73+ to W56+

Cited by in corpus (2)

• Dielectronic recombination of lanthanide and low ionization state tungsten ions: W${}^{13+}$ - W${}^{1+}$
• Dielectronic recombination of the open $4d$-shell of Tungsten: W${}^{37+}$ - W${}^{28+}$