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arXiv · 1710.06225

A project based on Multi-Configuration Dirac-Fock calculations for plasma spectroscopy

Maxime Comet·Jean-Christophe Pain·Franck Gilleron·Robin Piron
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Abstract

We present a project dedicated to hot plasma spectroscopy based on a Multi-Configuration Dirac-Fock (MCDF) code, initially developed by J. Bruneau. The code is briefly described and the use of the transition-state method for plasma spectroscopy is detailed. Then an opacity code for local-thermodynamic-equilibrium plasmas using MCDF data, named OPAMCDF, is presented. Transition arrays for which the number of lines is too large to be handled in a Detailed-Line-Accounting calculation can be modeled within the Partially-Resolved-Transition-Array method or using the Unresolved-Transition-Arrays formalism in jj-coupling. An improvement of the original Partially-Resolved-Transition-Array method is presented which gives a better agreement with Detailed-Line-Accounting computations. Comparisons with some absorption and emission experimental spectra are shown. Finally, the capability of the MCDF code to compute atomic data required for collisional-radiative modeling of plasma at non local thermodynamic equilibrium is illustrated. Additionally to photoexcitation, this code can be used to calculate photoionization, electron impact excitation and ionization cross-sections as well as autoionization rates in the Distorted-Wave or Close Coupling approximations. Comparisons with cross-sections and rates available in the literature are discussed.

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Maxime Comet, Jean-Christophe Pain, Franck Gilleron, Robin Piron. 2017-10-17. A project based on Multi-Configuration Dirac-Fock calculations for plasma spectroscopy. https://doi.org/10.1016/j.hedp.2017.05.010

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