Results 51 to 60 of about 152 (76)

Model for computing superconfiguration temperatures in nonlocal-thermodynamic-equilibrium hot plasmas

Physical Review E, 2004
A model is presented where the level-population densities in quasi-steady-state hot dense plasmas are described by means of large nonrelativistic superconfigurations (SC's), whose configuration populations follow a decreasing-exponential law versus energy (Boltzmann like) for a temperature depending on the SC.
J. Bauche, C. Bauche-Arnoult, K. B. Fournier   +2 more
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On the superconfiguration approach to model NLTE plasma emission

Journal of Quantitative Spectroscopy and Radiative Transfer, 2001
Abstract We discuss some aspects of the superconfiguration approach as applied to NLTE problems. The framework of this study is the AVERROES/TRANSPEC model developed for simulating non-LTE spectra. The model acts as a postprocessor to plasma hydrodynamics simulations.
O. Peyrusse
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Operator technique for calculating superconfiguration-averaged quantities of atoms in plasmas

Physical Review E, 1997
An operator technique for performing superconfiguration averages is presented. This technique is applicable in the calculation of local thermodynamic equilibrium (LTE) spectral moments as well as average rates for the various atomic processes in non-LTE collisional radiative models.
J. Oreg, A. Bar‐Shalom, M. Klapisch
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Stable method for the calculation of partition functions in the superconfiguration approach

Physical Review E, 2004
A general method for the calculation of the partition function of a canonical ensemble of noninteracting bound electrons is presented. It consists in a doubly recursive procedure with respect to the number of electrons and the number of orbitals. Contrary to existing approaches, this recursion relation contains no alternate summation of positive and ...
F. Gilleron, Jean‐Christophe Pain
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A superconfiguration code based on the local density approximation

Journal of Quantitative Spectroscopy and Radiative Transfer, 2000
Abstract The local density approximation (LDA) has been applied in a version of the SCO code based on the superconfiguration method. The self-consistent-field LDA equations for each superconfiguration are obtained by minimization of the free-energy functional with an appropriate number of constraints which guarantee the required populations of ...
T. Błeński, A. Grimaldi, F. Perrot
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The temperature law for superconfigurations in non-LTE plasmas

Journal of Quantitative Spectroscopy and Radiative Transfer, 2001
Abstract It is shown that, in non-LTE hot plasmas, the atomic processes tend to establish a temperature law, i.e., a decreasing-exponential law vs. energy, for the total atomic populations of the configurations within each superconfiguration (SC). The SCs are defined by the occupancy numbers of atomic shells.
C. Bauche-Arnoult, J. Bauche
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Non-LTE superconfiguration collisional radiative model

Journal of Quantitative Spectroscopy and Radiative Transfer, 1997
Abstract We have developed a non-LTE collisional radiative model which takes into account the overwhelming multiplicity of excited levels of heavy elements in hot and dense plasmas. The model, ‘SCROLL’ (Super Configuration Radiative cOLLisional), treats superconfigurations as effective levels and reproduces detailed configuration accounting results ...
A. Bar‐Shalom, J. Oreg, M. Klapisch
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Superconfigurations and Super Transition Arrays

, 2015
This chapter is a continuation of Chap. 6 in the sense that, for very complex ions, not only the number of levels is overwhelmingly large, but also the number of configurations. The concept of superconfiguration has been introduced for a proper gathering of configurations through the definition of supershells (collections of ordinary subshells).
J. Bauche, Claire Bauche‐Arnoult, O. Peyrusse   +2 more
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Calculation of plasma transmission spectra using the superconfiguration method with orbital relaxation effects

Journal of Quantitative Spectroscopy and Radiative Transfer, 1997
Abstract We describe a program developed at CEA Limeil-Valenton for the calculation of absorption spectra. This program is based on the idea of the Superconfiguration method proposed by Bar-Shalom et al. and implemented in their Super Transition Arrays code (STA).
F. Perrot, T. Błeński, A. Grimaldi
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Quantum mechanical model for the study of pressure ionization in the superconfiguration approach

Journal of Physics A: Mathematical and General, 2006
The knowledge of plasma equation of state and photoabsorption requires suitable and realistic models for the description of ions. The number of relevant electronic configurations of ions in hot dense plasmas can be immense (increasing with atomic number Z).
Jean‐Christophe Pain, G. Dejonghe, T. Błeński   +2 more
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