Partial and Total Dielectronic Recombination rate coefficients for W73+ to W56+

Abstract

Dielectronic recombination (DR) is a key atomic process which affects the spectroscopic diagnostic modelling of tungsten, most of whose ionization stages will be found somewhere in the ITER fusion reactor: in the edge, divertor, or core plasma. Accurate DR data is sparse while complete DR coverage is unsophisticated (e.g. average-atom or Burgess General Formula) as illustrated by the large uncertainties which currently exist in the tungsten ionization balance. To this end, we present a series of partial final state-resolved and total DR rate coefficients for W73+ to W56+ Tungsten ions. This is part of a wider effort within The Tungsten Project to calculate accurate dielectronic recombination rate coefficients for the tungsten isonuclear sequence for use in collisional-radiative modelling of finite-density tokamak plasmas. The recombination rate coefficients have been calculated with autostructure using kappa-averaged relativistic wavefunctions in level resolution (intermediate coupling) and configuration resolution (configuration average). The results are available from OPEN-ADAS according to the adf09 and adf48 standard formats. Comparison with previous calculations of total DR rate coefficients for W63+ and W56+ yield agreement to within 20% and 10%, respectively, at peak temperature. It is also seen that the Juttner correction to the Maxwell distribution has a significant effect on the ionization balance of tungsten at the highest charge states, changing both the peak abundance temperatures and the ionization fractions of several ions.

arXiv comment36 pages, 23 figures. Accepted for publication in Physical Review A

References in corpus (4)

• Dielectronic recombination data for dynamic finite-density plasmas I. Goals and methodology
• Radiative recombination data for modelling dynamic finite-density plasmas
• Calculations of Energy Losses due to Atomic Processes in Tokamaks with Applications to the ITER Divertor
• Recombination of W18+ ions with electrons: Absolute rate coefficients from a storage-ring experiment and from theoretical calculations

Cited by in corpus (5)

• Dielectronic recombination of lanthanide and low ionization state tungsten ions: W${}^{13+}$ - W${}^{1+}$
• Recombination of open-f-shell tungsten ions
• Dielectronic recombination of the open $4d$-shell of Tungsten: W${}^{37+}$ - W${}^{28+}$
• Partial and Total Dielectronic Recombination Rate Coefficients for W${}^{55+}$ to W${}^{38+}$
• The Tungsten Project: Dielectronic Recombination Data For Collisional-Radiative Modelling In ITER