Special Issue "Spectral Line Shapes in Plasmas"

Quicklinks

A special issue of Atoms (ISSN 2218-2004).

Deadline for manuscript submissions: closed (31 March 2014)

Special Issue Editors

Guest Editor
Dr. Evgeny Stambulchik (Website)

Plasma Laboratory, Weizmann Institute of Science, Rehovot 7610001 Israel
Phone: 972-8-9343610
Fax: 972-8-9343491
Interests: line-shape broadening in plasmas; Stark and Zeeman effects; polarization spectroscopy; non-LTE kinetics in plasmas
Guest Editor
Dr. Hyun-Kyung Chung

International Atomic Energy Agency, Atomic and Molecular Data Unit, Nuclear Data Section, P.O. Box 100, A-1400 Vienna, Austria
Phone: +43 1 2600 21729
Fax: +43 1 26007
Interests: atomic, molecular and plasma-surface interaction data for fusion applications; atomic processes in plasmas; non-LTE kinetics in plasmas; radiative properties of hot dense matter; plasma spectroscopy modeling
Guest Editor
Dr. Annette Calisti

Laboratoire PIIM, UMR7345,Aix-Marseille Université - CNRS,Centre Saint Jérôme case 232, 13397 Marseille Cedex 20, France
Phone: +33(0)491282719
Guest Editor
Dr. Manuel Á. González Delgado

Departamento de Física Aplicada, Escuela Técnica Superior de Ingeniería Informática, Universidad de Valladolid, Paseo de Belén 15, 47011 Valladolid, Spain
Interests: atomic line shape calculation; plasma diagnostics; computer simulation; mLearning; biometrics

Special Issue Information

Line-shape analysis is one of the most important tools for diagnostics of both laboratory and space plasmas. Its reliable implementation requires sufficiently accurate calculations, which imply the use of analytical methods and computer codes of varying complexity, and, necessarily, varying limits of applicability and accuracy. However, studies comparing different computational and analytical methods are almost nonexistent. The Spectral Line Shapes in Plasma (SLSP) code comparison workshop series was established to fill this gap.

Numerous computational cases considered in the two workshops organized to date (in 2012 and 2013) not only served the purpose of code comparison, but also have applications in research of magnetic fusion, astrophysical and laser-produced plasmas, and more. Therefore, although the first workshop was shortly reviewed elsewhere[1], and will likely be followed by a review of the second one, it was unanimously decided by the participants that a dedicated volume devoted to results of the workshops is desired. It is the purpose of this special issue.

In addition, we welcome contributions from the wider community working on diverse aspects of calculations of spectral line shapes in plasmas.

[1] E. Stambulchik, High Energy Density Phys. 9, 528-534 (2013).

Submission

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. Papers will be published continuously (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are refereed through a peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Atoms is an international peer-reviewed Open Access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. For the first couple of issues the Article Processing Charge (APC) will be waived for well-prepared manuscripts. English correction and/or formatting fees of 250 CHF (Swiss Francs) will be charged in certain cases for those articles accepted for publication that require extensive additional formatting and/or English corrections.

Print Edition available!
A Print Edition of this Special Issue is available here.

Name Pice* Download or order
Spectral Line Shapes in Plasmas 40.00 CHF here
For contributing authors or bulk orders special prices may apply.
Prices include shipping.

Keywords

spectral line shapes; line broadening; Stark effect; Zeeman effect; code comparison


Published Papers (13 papers)

View options order results:
result details:
Displaying articles 1-13
Export citation of selected articles as:

Editorial

Jump to: Research, Review

Open AccessEditorial Special Issue on Spectral Line Shapes in Plasmas
Atoms 2014, 2(3), 378-381; doi:10.3390/atoms2030378
Received: 16 July 2014 / Accepted: 17 July 2014 / Published: 7 August 2014
Cited by 1 | PDF Full-text (113 KB) | HTML Full-text | XML Full-text
Abstract
Line-shape analysis is one of the most important tools for diagnostics of both laboratory and space plasmas. Its reliable implementation requires sufficiently accurate calculations, which imply the use of analytic methods and computer codes of varying complexity, and, necessarily, varying limits of [...] Read more.
Line-shape analysis is one of the most important tools for diagnostics of both laboratory and space plasmas. Its reliable implementation requires sufficiently accurate calculations, which imply the use of analytic methods and computer codes of varying complexity, and, necessarily, varying limits of applicability and accuracy. However, studies comparing different computational and analytic methods are almost non-existent. The Spectral Line Shapes in Plasma (SLSP) code comparison workshop series [1] was established to fill this gap. Numerous computational cases considered in the two workshops organized to date (in April 2012 and August 2013 in Vienna, Austria) not only serve the purpose of code comparison, but also have applications in research of magnetic fusion, astrophysical, laser-produced plasmas, and so on. Therefore, although the first workshop was briefly reviewed elsewhere [2], and will likely be followed by a review of the second one, it was unanimously decided by the participants that a volume devoted to results of the workshops was desired. It is the main purpose of this special issue. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available

Research

Jump to: Editorial, Review

Open AccessArticle On the Application of Stark Broadening Data Determined with a Semiclassical Perturbation Approach
Atoms 2014, 2(3), 357-377; doi:10.3390/atoms2030357
Received: 5 May 2014 / Revised: 20 June 2014 / Accepted: 16 July 2014 / Published: 7 August 2014
Cited by 4 | PDF Full-text (263 KB) | HTML Full-text | XML Full-text
Abstract The significance of Stark broadening data for problems in astrophysics, physics, as well as for technological plasmas is discussed and applications of Stark broadening parameters calculated using a semiclassical perturbation method are analyzed. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle Spectral-Kinetic Coupling and Effect of Microfield Rotation on Stark Broadening in Plasmas
Atoms 2014, 2(3), 334-356; doi:10.3390/atoms2030334
Received: 13 May 2014 / Revised: 17 June 2014 / Accepted: 2 July 2014 / Published: 30 July 2014
Cited by 4 | PDF Full-text (1514 KB) | HTML Full-text | XML Full-text
Abstract
The study deals with two conceptual problems in the theory of Stark broadening by plasmas. One problem is the assumption of the density matrix diagonality in the calculation of spectral line profiles. This assumption is closely related to the definition of zero [...] Read more.
The study deals with two conceptual problems in the theory of Stark broadening by plasmas. One problem is the assumption of the density matrix diagonality in the calculation of spectral line profiles. This assumption is closely related to the definition of zero wave functions basis within which the density matrix is assumed to be diagonal, and obviously violated under the basis change. A consistent use of density matrix in the theoretical scheme inevitably leads to interdependence of atomic kinetics, describing the population of atomic states with the Stark profiles of spectral lines, i.e., to spectral-kinetic coupling. The other problem is connected with the study of the influence of microfield fluctuations on Stark profiles. Here the main results of the perturbative approach to ion dynamics, called the theory of thermal corrections (TTC), are presented, within which the main contribution to effects of ion dynamics is due to microfield fluctuations caused by rotations. In the present study the qualitative behavior of the Stark profiles in the line center within predictions of TTC is confirmed, using non-perturbative computer simulations. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle Line-Shape Code Comparison through Modeling and Fitting of Experimental Spectra of the C ii 723-nm Line Emitted by the Ablation Cloud of a Carbon Pellet
Atoms 2014, 2(3), 319-333; doi:10.3390/atoms2030319
Received: 9 May 2014 / Revised: 28 May 2014 / Accepted: 25 June 2014 / Published: 14 July 2014
Cited by 3 | PDF Full-text (820 KB) | HTML Full-text | XML Full-text
Abstract
Various codes of line-shape modeling are compared to each other through the profile of the C ii 723-nm line for typical plasma conditions encountered in the ablation clouds of carbon pellets, injected in magnetic fusion devices. Calculations were performed for a single [...] Read more.
Various codes of line-shape modeling are compared to each other through the profile of the C ii 723-nm line for typical plasma conditions encountered in the ablation clouds of carbon pellets, injected in magnetic fusion devices. Calculations were performed for a single electron density of 1017 cm−3 and two plasma temperatures (T = 2 and 4 eV). Ion and electron temperatures were assumed to be equal (Te = Ti = T). The magnetic field, B, was set equal to either to zero or 4 T. Comparisons between the line-shape modeling codes and two experimental spectra of the C ii 723-nm line, measured perpendicularly to the B-field in the Large Helical Device (LHD) using linear polarizers, are also discussed. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle Ion Dynamics Effect on Stark-Broadened Line Shapes: A Cross-Comparison of Various Models
Atoms 2014, 2(3), 299-318; doi:10.3390/atoms2030299
Received: 30 April 2014 / Revised: 10 June 2014 / Accepted: 16 June 2014 / Published: 4 July 2014
Cited by 14 | PDF Full-text (611 KB) | HTML Full-text | XML Full-text
Abstract
Modeling the Stark broadening of spectral lines in plasmas is a complex problem. The problem has a long history, since it plays a crucial role in the interpretation of the observed spectral lines in laboratories and astrophysical plasmas. One difficulty is the [...] Read more.
Modeling the Stark broadening of spectral lines in plasmas is a complex problem. The problem has a long history, since it plays a crucial role in the interpretation of the observed spectral lines in laboratories and astrophysical plasmas. One difficulty is the characterization of the emitter’s environment. Although several models have been proposed over the years, there have been no systematic studies of the results, until now. Here, calculations from stochastic models and numerical simulations are compared for the Atoms 2014, 2 300 Lyman-α and -β lines in neutral hydrogen. Also discussed are results from the Helium-α and -β lines of Ar XVII. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle Spectral Line Shapes of He I Line 3889 Å
Atoms 2014, 2(2), 277-298; doi:10.3390/atoms2020277
Received: 31 March 2014 / Revised: 5 June 2014 / Accepted: 10 June 2014 / Published: 23 June 2014
Cited by 3 | PDF Full-text (489 KB) | HTML Full-text | XML Full-text
Abstract
Spectral line shapes of neutral helium 3889 Å(23S–33P) transition line are calculated by using several theoretical methods. The electronic contribution to the line broadening is calculated from quantum statistical many-particle theory by using thermodynamic Green's function, including dynamic [...] Read more.
Spectral line shapes of neutral helium 3889 Å(23S–33P) transition line are calculated by using several theoretical methods. The electronic contribution to the line broadening is calculated from quantum statistical many-particle theory by using thermodynamic Green's function, including dynamic screening of the electron-atom interaction. The ionic contribution is taken into account in a quasistatic approximation, where a static microfield distribution function is presented. Strong electron collisions are consistently considered with an effective two-particle T-matrix approach, where Convergent Close Coupling method gives scattering amplitudes including Debye screening for neutral helium. Then the static profiles converted to dynamic profiles by using the Frequency Fluctuation Model. Furthermore, Molecular Dynamics simulations for interacting and independent particles are used where the dynamic sequence of microfield is taken into account. Plasma parameters are diagnosed and good agreements are shown by comparing our theoretical results with the recent experimental result of Jovićević et al. (J. Phys. B: At. Mol. Opt. Phys. 2005, 38, 1249). Additionally, comparison with various experimental data in a wide range of electron density ne ≈ (1022− 1024)m−3 and temperature T ≈ (2−6) × 104 K are presented. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle Ideal Coulomb Plasma Approximation in Line Shape Models: Problematic Issues
Atoms 2014, 2(2), 253-258; doi:10.3390/atoms2020253
Received: 23 March 2014 / Revised: 11 June 2014 / Accepted: 13 June 2014 / Published: 19 June 2014
Cited by 4 | PDF Full-text (125 KB) | HTML Full-text | XML Full-text
Abstract
In weakly coupled plasmas, it is common to describe the microfield using a Debye model. We examine here an “artificial” ideal one-component plasma with an infinite Debye length, which has been used for the test of line shape codes. We show that [...] Read more.
In weakly coupled plasmas, it is common to describe the microfield using a Debye model. We examine here an “artificial” ideal one-component plasma with an infinite Debye length, which has been used for the test of line shape codes. We show that the infinite Debye length assumption can lead to a misinterpretation of numerical simulations results, in particular regarding the convergence of calculations. Our discussion is done within an analytical collision operator model developed for hydrogen line shapes in near-impact regimes. When properly employed, this model can serve as a reference for testing the convergence of simulations. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle Influence of Microfield Directionality on Line Shapes
Atoms 2014, 2(2), 259-276; doi:10.3390/atoms2020259
Received: 15 April 2014 / Revised: 2 June 2014 / Accepted: 5 June 2014 / Published: 19 June 2014
Cited by 5 | PDF Full-text (1545 KB) | HTML Full-text | XML Full-text
Abstract
In the framework of the Spectral Line Shapes in Plasmas Code Comparison Workshop (SLSP), large discrepancies appeared between the different approaches to account for ion motion effects in spectral line shape calculations. For a better understanding of these effects, in the second [...] Read more.
In the framework of the Spectral Line Shapes in Plasmas Code Comparison Workshop (SLSP), large discrepancies appeared between the different approaches to account for ion motion effects in spectral line shape calculations. For a better understanding of these effects, in the second edition of the SLSP in August, 2013, two cases were dedicated to the study of the ionic field directionality on line shapes. In this paper, the effects of the direction and magnitude fluctuations are separately analyzed. The effects of two variants of electric field models, (i) a pure rotating field with constant magnitude and (ii) a time-dependent magnitude field in a given direction, together with the effects of the time-dependent ionic field on shapes of the He II Lyman-α and -β lines for different densities and temperatures, are discussed. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle Widths and Shifts of Isolated Lines of Neutral and Ionized Atoms Perturbed by Collisions With Electrons and Ions: An Outline of the Semiclassical Perturbation (SCP) Method and of the Approximations Used for the Calculations
Atoms 2014, 2(2), 225-252; doi:10.3390/atoms2020225
Received: 24 April 2014 / Revised: 22 May 2014 / Accepted: 26 May 2014 / Published: 10 June 2014
Cited by 13 | PDF Full-text (450 KB) | HTML Full-text | XML Full-text
Abstract
“Stark broadening” theory and calculations have been extensively developed for about 50 years. The theory can now be considered as mature for many applications, especially for accurate spectroscopic diagnostics and modeling, in astrophysics, laboratory plasma physics and technological plasmas, as well. This [...] Read more.
“Stark broadening” theory and calculations have been extensively developed for about 50 years. The theory can now be considered as mature for many applications, especially for accurate spectroscopic diagnostics and modeling, in astrophysics, laboratory plasma physics and technological plasmas, as well. This requires the knowledge of numerous collisional line profiles. In order to meet these needs, the “SCP” (semiclassical perturbation) method and numerical code were created and developed. The SCP code is now extensively used for the needs of spectroscopic diagnostics and modeling, and the results of the published calculations are displayed in the STARK-B database. The aim of the present paper is to introduce the main approximations leading to the impact of semiclassical perturbation method and to give formulae entering the numerical SCP code, in order to understand the validity conditions of the method and of the results; and also to understand some regularities and systematic trends. This would also allow one to compare the method and its results to those of other methods and codes. 1 Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Figures

Open AccessArticle Electron-Impact Widths and Shifts of B III 2p-2s Lines
Atoms 2014, 2(2), 207-214; doi:10.3390/atoms2020207
Received: 17 March 2014 / Revised: 23 April 2014 / Accepted: 5 May 2014 / Published: 15 May 2014
Cited by 2 | PDF Full-text (221 KB) | HTML Full-text | XML Full-text
Abstract
In this paper, we present results for the relativistic quantum mechanical calculations of electron-impact line widths and shifts of 2p-2s transitions in doubly ionized boron (B III) ions. We use the Dirac R-matrix methods to solve (N + 1)-electron colliding systems for [...] Read more.
In this paper, we present results for the relativistic quantum mechanical calculations of electron-impact line widths and shifts of 2p-2s transitions in doubly ionized boron (B III) ions. We use the Dirac R-matrix methods to solve (N + 1)-electron colliding systems for the scattering matrices that are required. The line widths are calculated for an electron density 1:81 × 1018 cm-3 and electron temperature 10:6 eV. The obtained results agree well with all the semiempirical calculations and most of the semiclassical calculations, and are closer to the experimental results published by Glenzer and Kunze (Glenzer, S.; Kunze, H.-J. Stark broadening of resonance transitions in B III. Phys. Rev. A 1996, 53, 2225–2229). Our line widths are almost twice as large as the earlier quantum mechanical calculations for the set of particular plasma conditions. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessArticle The Second Workshop on Lineshape Code Comparison: Isolated Lines
Atoms 2014, 2(2), 157-177; doi:10.3390/atoms2020157
Received: 14 March 2014 / Revised: 9 April 2014 / Accepted: 25 April 2014 / Published: 12 May 2014
Cited by 6 | PDF Full-text (147 KB) | HTML Full-text | XML Full-text
Abstract In this work, we briefly summarize the theoretical aspects of isolated line broadening. We present and discuss test run comparisons from different participating lineshape codes for the 2s-2p transition for LiI, B III and NV. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available

Review

Jump to: Editorial, Research

Open AccessReview Hydrogen Spectral Line Shape Formation in the SOL of Fusion Reactor Plasmas
Atoms 2014, 2(2), 195-206; doi:10.3390/atoms2020195
Received: 28 March 2014 / Revised: 6 May 2014 / Accepted: 6 May 2014 / Published: 15 May 2014
Cited by 3 | PDF Full-text (791 KB) | HTML Full-text | XML Full-text
Abstract
The problems related to the spectral line-shape formation in the scrape of layer (SOL) in fusion reactor plasma for typical observation chords are considered. The SOL plasma is characterized by the relatively low electron density (1012–1013 cm−3) [...] Read more.
The problems related to the spectral line-shape formation in the scrape of layer (SOL) in fusion reactor plasma for typical observation chords are considered. The SOL plasma is characterized by the relatively low electron density (1012–1013 cm−3) and high temperature (from 10 eV up to 1 keV). The main effects responsible for the line-shape formation in the SOL are Doppler and Zeeman effects. The main problem is a correct modeling of the neutral atom velocity distribution function (VDF). The VDF is determined by a number of atomic processes, namely: molecular dissociation, ionization and charge exchange of neutral atoms on plasma ions, electron excitation accompanied by the charge exchange from atomic excited states, and atom reflection from the wall. All the processes take place step by step during atom motion from the wall to the plasma core. In practice, the largest contribution to the neutral atom radiation emission comes from a thin layer near the wall with typical size 10–20 cm, which is small as compared with the minor radius of modern devices including international test experimental reactor ITER (radius 2 m). The important problem is a strongly non-uniform distribution of plasma parameters (electron and ion densities and temperatures). The distributions vary for different observation chords and ITER operation regimes. In the present report, most attention is paid to the problem of the VDF calculations. The most correct method for solving the problem is an application of the Monte Carlo method for atom motion near the wall. However, the method is sometimes too complicated to be combined with other numerical codes for plasma modeling for various regimes of fusion reactor operation. Thus, it is important to develop simpler methods for neutral atom VDF in space coordinates and velocities. The efficiency of such methods has to be tested via a comparison with the Monte Carlo codes for particular plasma conditions. Here a new simplified method for description of neutral atoms penetration into plasma is suggested. The method is based on the ballistic motion of neutrals along the line-of-sight (LoS) in the forward–back approximation. As a result, two-dimensional distribution functions, dependent on the LoS coordinate and the velocity projection on the LoS, and responsible for the Doppler broadening of the line shape, are calculated. A comparison of the method with Monte Carlo calculations allows the evaluation of the accuracy of the ballistic model. The Balmer spectral line shapes are calculated for specific LoS typical for ITER diagnostics. Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available
Open AccessReview Review of Langmuir-Wave-Caused Dips and Charge-Exchange-Caused Dips in Spectral Lines from Plasmas and their Applications
Atoms 2014, 2(2), 178-194; doi:10.3390/atoms2020178
Received: 22 January 2014 / Revised: 25 March 2014 / Accepted: 30 April 2014 / Published: 13 May 2014
Cited by 4 | PDF Full-text (506 KB) | HTML Full-text | XML Full-text
Abstract
We review studies of two kinds of dips in spectral line profiles emitted by plasmas—dips that have been predicted theoretically and observed experimentally: Langmuir-wave-caused dips (L-dips) and charge-exchange-caused dips (X-dips). There is a principal difference with respect to positions of L-dips and [...] Read more.
We review studies of two kinds of dips in spectral line profiles emitted by plasmas—dips that have been predicted theoretically and observed experimentally: Langmuir-wave-caused dips (L-dips) and charge-exchange-caused dips (X-dips). There is a principal difference with respect to positions of L-dips and X-dips relative to the unperturbed wavelength of a spectral line: positions of L-dips scale with the electron density Ne roughly as Ne1/2, while positions of X-dips are almost independent of Ne (the dependence is much weaker than for L-dips). L-dips and X-dips phenomena are important, both fundamentally and practically. The fundamental importance is due to a rich physics behind each of these phenomena. L-dips are a multi-frequency resonance phenomenon caused by a single-frequency (monochromatic) electric field. X-dips are due to charge exchange at anticrossings of terms of a diatomic quasi-molecule, whose nuclei have different charges. As for important practical applications, they are as follows: observations of L-dips constitute a very accurate method to measure the electron density in plasmas—a method that does not require knowledge of the electron temperature. L-dips also allow measuring the amplitude of the electric field of Langmuir waves—the only spectroscopic method available for this purpose. Observations of X-dips provide an opportunity to determine rate coefficient of charge exchange between multi-charged ions. This is an important reference data, virtually inaccessible by other experimental methods. The rate coefficients of charge exchange are important for magnetic fusion in Tokamaks, for population inversion in the soft x-ray and VUV ranges, for ion storage devices, as well as for astrophysics (e.g., for the solar plasma and for determining the physical state of planetary nebulae). Full article
(This article belongs to the Special Issue Spectral Line Shapes in Plasmas) Print Edition available

Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

 

Journal Contact

MDPI AG
Atoms Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
atoms@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Atoms
Back to Top