Spectral Line Shapes in Plasmas Edited by Evgeny Stambulchik, Annette Calisti, Hyun-Kyung Chung and Manuel Á. González Printed Edition of the Special Issue Published in Atoms www.mdpi.com/journal/atoms Evgeny Stambulchik, Annette Calisti, Hyun-Kyung Chung and Manuel Á. González (Eds.) Spectral Line Shapes in Plasmas This book is a reprint of the special issue that appeared in the online open access journal Atoms (ISSN 2218-2004) in 2014 (available at: http://www.mdpi.com/journal/atoms/special_issues/SpectralLineShapes). Guest Editors Evgeny Stambulchik Hyun-Kyung Chung Department of Particle Physics International Atomic Energy Agency, Atomic and and Astrophysics, Molecular Data Unit, Nuclear Data Section, P.O. Faculty of Physics, Box 100, A-1400 Vienna, Austria Weizmann Institute of Science, Rehovot 7610001, Israel Annette Calisti Manuel Á. González Laboratoire PIIM, UMR7345, Departamento de Física Aplicada, Escuela Técnica Aix-Marseille Université - CNRS, Superior de Ingeniería Informática, Centre Saint Jérôme case 232, Universidad de Valladolid, Paseo de Belén 15, 13397 Marseille Cedex 20, France 47011 Valladolid, Spain Editorial Office Publisher Production Editor MDPI AG Shu-Kun Lin Martyn Rittman Klybeckstrasse 64 4057 Basel, Switzerland 1. Edition 2015 MDPI • Basel • Beijing • Wuhan ISBN 978-3-906980-82-9 © 2015 by the authors; licensee MDPI AG, Basel, Switzerland. All articles in this volume are Open Access distributed under the Creative Commons Attribution 3.0 license (http://creativecommons.org/licenses/by/3.0/), which allows users to download, copy and build upon published articles, even for commercial purposes, as long as the author and publisher are properly credited. The dissemination and distribution of copies of this book as a whole, however, is restricted to MDPI AG, Basel, Switzerland. III Table of Contents Evgeny Stambulchik, Annette Calisti, Hyun-Kyung Chung and Manuel Á. González (Eds.) Preface .................................................................................................................................. V Hydrogen-Like Transitions Sandrine Ferri, Annette Calisti, Caroline Mossé, Joël Rosato, Bernard Talin, Spiros Alexiou, Marco A. Gigosos, Manuel A. González, Diego González-Herrero, Natividad Lara, Thomas Gomez, Carlos Iglesias, Sonja Lorenzen, Roberto C. Mancini and Evgeny Stambulchik Ion Dynamics Effect on Stark-Broadened Line Shapes: A Cross-Comparison of Various Models Reprinted from: Atoms 2014, 2(3), 299-318 ............................................................................ 1 http://www.mdpi.com/2218-2004/2/3/299 Annette Calisti, Alexander V. Demura, Marco A. Gigosos, Diego González-Herrero, Carlos A. Iglesias, Valery S. Lisitsa and Evgeny Stambulchik Influence of Microfield Directionality on Line Shapes Reprinted from: Atoms 2014, 2(2), 259-276 .......................................................................... 22 http://www.mdpi.com/2218-2004/2/2/259 Alexander V. Demura and Evgeny Stambulchik Spectral-Kinetic Coupling and Effect of Microfield Rotation on Stark Broadening in Plasmas Reprinted from: Atoms 2014, 2(3), 334-356 .......................................................................... 40 http://www.mdpi.com/2218-2004/2/3/334 Joel Rosato, Hubert Capes and Roland Stamm Ideal Coulomb Plasma Approximation in Line Shape Models: Problematic Issues Reprinted from: Atoms 2014, 2(2), 253-258 .......................................................................... 64 http://www.mdpi.com/2218-2004/2/2/253 Isolated Lines Spiros Alexiou, Milan S. Dimitrijevi(cid:252), Sylvie Sahal-Brechot, Evgeny Stambulchik, Bin Duan, Diego González-Herrero and Marco A. Gigosos The Second Workshop on Lineshape Code Comparison: Isolated Lines Reprinted from: Atoms 2014, 2(2), 157-177 .......................................................................... 70 http://www.mdpi.com/2218-2004/2/2/157 IV Sylvie Sahal-Bréchot, Milan S. Dimitrijevi(cid:252) and Nabil Ben Nessib 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 Reprinted from: Atoms 2014, 2(2), 225-252 .......................................................................... 91 http://www.mdpi.com/2218-2004/2/2/225 Bin Duan, Muhammad Abbas Bari, Zeqing Wu and Jun Yan Electron-Impact Widths and Shifts of B III 2p-2s Lines Reprinted from: Atoms 2014, 2(2), 207-214 ........................................................................ 120 http://www.mdpi.com/2218-2004/2/2/207 Mohammed Koubiti, Motoshi Goto, Sandrine Ferri, Stephanie B. Hansen and Evgeny Stambulchik 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 Reprinted from: Atoms 2014, 2(3), 319-333 ........................................................................ 129 http://www.mdpi.com/2218-2004/2/3/319 Applications Milan S. Dimitrijevi(cid:252) and Sylvie Sahal-Bréchot On the Application of Stark Broadening Data Determined with a Semiclassical Perturbation Approach Reprinted from: Atoms 2014, 2(3), 357-377 ........................................................................ 145 http://www.mdpi.com/2218-2004/2/3/357 Banaz Omar, Manuel Á. González, Marco A. Gigosos, Tlekkabul S. Ramazanov, Madina C. Jelbuldina, Karlygash N. Dzhumagulova, Mark C. Zammit, Dmitry V. Fursa and Igor Bray Spectral Line Shapes of He I Line 3889 Å Reprinted from: Atoms 2014, 2(2), 277-298 ........................................................................ 166 http://www.mdpi.com/2218-2004/2/2/277 Valery S. Lisitsa, Mikhail B. Kadomtsev, Vladislav Kotov, Vladislav S. Neverov and Vladimir A. Shurygin Hydrogen Spectral Line Shape Formation in the SOL of Fusion Reactor Plasmas Reprinted from: Atoms 2014, 2(2), 195-206 ........................................................................ 189 http://www.mdpi.com/2218-2004/2/2/195 Elisabeth Dalimier, Eugene Oks and Oldrich Renner Review of Langmuir-Wave-Caused Dips and Charge-Exchange-Caused Dips in Spectral Lines from Plasmas and their Applications Reprinted from: Atoms 2014, 2(2), 178-194 ........................................................................ 202 http://www.mdpi.com/2218-2004/2/2/178 V Preface 1. Foreword 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. 2. Hydrogen-Like Transitions Many calculation cases suggested for the first two SLSP workshops are for simple atomic systems: the hydrogen atom or hydrogen-like one-electron ions. Of these, the Ly-_ transition is truly the simplest; the atomic model was further reduced by neglecting the fine structure and interactions between states with different principal quantum numbers. Interestingly, this simplest system caused the largest discrepancies between results of various models presented at the first workshop [2] due to, apparently, different treatments of the ion dynamics effect. Now, Ferri et al. [3] discuss this, extending the analysis to more complex transitions with forbidden components. The ion dynamics effect is intimately related to the microfield directionality, as studied in depth by Calisti et al. [4]. Notably, the effects of the directionality of the microfield fluctuations were first researched within the framework of the “standard theory” of the plasma line broadening almost four decades ago, but have largely been forgotten. This approach is recalled and comparisons with computer simulations are made in the paper by Demura and Stambulchik [5]. Results of computer simulations will indeed be found in a majority of studies in this volume. By many scholars, such calculations are considered ab initio and their results regarded as benchmarks—at least for hydrogen-like transitions. However, Rosato et al. [6] argue that caution should be exercised in the case of very weakly coupled plasmas; in the extreme limit of the ideal plasma model, even the largest supercomputers available today might not be able to achieve convergence. VI 3. Isolated Lines Isolated lines are often contradistinguished from radiative transitions in hydrogen-like species with degenerate energy levels. Alexiou et al. [7] briefly summarize the theoretical aspects of isolated-line broadening and then delve into a detailed comparison of Stark widths and shifts of Li-like 2s–2p transitions as calculated by various approaches. One of these approaches is the semiclassical perturbation (SCP) method, the work horse behind the STARK- B database. A complete up-to-date description of SCP is presented by Sahal-Bréchot et al. [8]. Another approach, also included in the comparison [7], is based on the relativistic Dirac R- matrix method, and is described by Duan et al. [9] with a focus on the B III 2s–2p doublet. Koubiti et al. [10] present a comparison of various line-shape computational methods applied to the case of a plasma-broadened isolated line subjected to magnetic field. Furthermore, this study covers one of the two challenges introduced at the second SLSP workshop, where participants were asked to explain previously unpublished experimental data based on best-fit spectra of their models. 4. Applications One can hardly overestimate the significance of line-shape calculations for diagnostics of laboratory, space, and industrial plasmas. Dimitrijevi(cid:252) and Sahal-Bréchot [11] show and discuss numerous examples of such studies, where the SCP approach [8] was used. In the article of Omar et al. [12], the authors use a few theoretical methods and computer simulations to calculate the shapes of a He I line and compare them to experimental line profiles, allowing inference of the plasma parameters. Lisitsa et al. [13] introduce a new method able to describe penetration of a neutral atomic beam into low-density inhomogeneous fusion plasmas, and provide sample calculations suitable for ITER diagnostics. Spectral line features caused by Langmuir waves and charge-exchange processes are discussed by Dalimier et al. [14], who also suggest several spectral lines for prospective studies of laser-produced plasmas. 5. Conclusions For the first two SLSP workshops, participants submitted in total over 1,500 line-shape calculations. The studies collected in this Special Issue explore only a part of this immense work. Research is ongoing, and we expect more publications soon. The next workshop is scheduled for March 2015 in Marseille, France [1]. Evgeny Stambulchik, Annette Calisti, Hyun-Kyung Chung and Manuel Á. González Guest Editors Reprinted from Atoms. Cite as: Stambulchik, E.; Calisti, A.; Chung, H.-K.; González, M.A. Special Issue on Spectral Line Shapes in Plasmas. Atoms 2014, 2, 378-381. VII Acknowledgements The organizational and financial support from the International Atomic Energy Agency for conducting the SLSP workshops is highly appreciated. Conflicts of Interest The authors declare no conflict of interest. References 1. Spectral Line Shapes in Plasmas workshops. Available online: http://plasmagate.weizmann. ac.il/slsp/ (accessed on 16 July 2014). 2. Stambulchik, E. Review of the 1st Spectral Line Shapes in Plasmas code comparison workshop. High Energy Density Phys. 2013, 9, 528–534. 3. Ferri, S.; Calisti, A.; Mossé, C.; Rosato, J.; Talin, B.; Alexiou, S.; Gigosos, M.A.; González, M.Á.; González-Herrero, D.; Lara, N.; Gomez, T.; Iglesias, C.A.; Lorenzen, S.; Mancini, R.C.; Stambulchik, E. Ion dynamics effect on Stark broadened line shapes: A cross comparison of various models. Atoms 2014, 2, 299–318. 4. Calisti, A.; Demura, A.; Gigosos, M.A.; González-Herrero, D.; Iglesias, C.A.; Lisitsa, V.S.; Stambulchik, E. Influence of microfield directionality on line shapes. Atoms 2014, 2, 259–276. 5. Demura, A.; Stambulchik, E. Spectral-kinetic coupling and effect of microfield rotation on Stark broadening in plasmas. Atoms 2014, 2, 334–356. 6. Rosato, J.; Capes, H.; Stamm, R. Ideal Coulomb plasma approximation in line shape models: Problematic issues. Atoms 2014, 2, 253–258. 7. Alexiou, S.; Dimitrijevi(cid:252), M.S.; Sahal-Brechot, S.; Stambulchik, E.; Duan, B.; González Herrero, D.; Gigosos, M.A. The Second Workshop on Lineshape Code Comparison: Isolated lines. Atoms 2014, 2, 157–177. 8. Sahal-Bréchot, S.; Dimitrijevi(cid:252), M.S.; Ben Nessib, N. 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, 225–252. 9. Duan, B.; Bari, M.A.; Wu, Z.; Yan, J. Electron-impact widths and shifts of B III 2p–2s lines. Atoms 2014, 2, 207–214. 10. Koubiti, M.; Goto, M.; Ferri, S.; Hansen, S.; Stambulchik, E. 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, 319–333. 11. Dimitrijevi(cid:252), M.S.; Sahal-Bréchot, S. On the application of Stark broadening data determined with Semiclassical Perturbation approach. Atoms 2014, 2, 357–377. 12. Omar, B.; González, M.Á.; Gigosos, M.A.; Ramazanov, T.S.; Jelbuldina, M.C.; Dzhumagulova, K.N.; Zammit, M.C.; Fursa, D.V.; Bray, I. Spectral line shapes of He I line 3889 Å. Atoms 2014, 2, 277–298. VIII 13. Lisitsa, V.S.; Kadomtsev, M.B.; Kotov, V.; Neverov, V.S.; Shurygin, V.A. Hydrogen spectral line shape formation in the SOL of fusion reactor plasmas. Atoms 2014, 2, 195–206. 14. Dalimier, E.; Oks, E.; Renner, O. Review of Langmuir-wave-caused dips and charge exchange-caused dips in spectral lines from plasmas and their applications. Atoms 2014, 2, 178–194. 1 Reprinted from Atoms. Cite as: Ferri, S.; Calisti, A.; Moss, C.; Rosato, J.; Talin, B.; Alexiou, S.; Gigosos, M.A.; González, M.A.; González-Herrero, D.; Lara, N.; et al. Ion Dynamics Effect on Stark-BroadenedLineShapes: ACross-ComparisonofVariousModels. Atoms2014,2,299-318. Article Ion Dynamics Effect on Stark-Broadened Line Shapes: A Cross-Comparison of Various Models SandrineFerri1,*,AnnetteCalisti1,CarolineMossé1,JoëlRosato1,BernardTalin1, SpirosAlexiou2,MarcoA.Gigosos3,ManuelA.González3,DiegoGonzález-Herrero3, NatividadLara3,ThomasGomez4,CarlosIglesias5,SonjaLorenzen6,RobertoC.Mancini7 andEvgenyStambulchik8 1Aix-MarseilleUniversité,CNRS,PIIMUMR7345,13397Marseille,France; E-Mails: [email protected](A.C.);[email protected](C.M.); [email protected](J.R.);[email protected](B.T.) 2TETY,UniversityofCrete,71409Heraklion,TK2208,Greece;E-Mail: [email protected](S.A.) 3DepartmentdeÓpticayFísicaApplicada,UniversidaddeValladolid,Valladolid47071,Spain; E-Mails: [email protected](M.A.G.);[email protected](M.A.G.); [email protected](D.G.-H.);[email protected](N.L.) 4DepartmentofAstronomy,UniversityofTexas,Austin,TX78731,USA; E-Mail: [email protected](T.G.) 5LLNL,Livermore,CA94550,USA;E-Mail: [email protected](C.I.) 6InstitutfürPhysik,UniversitätRostock,D-18051Rostock,Germany; E-Mail: [email protected](S.L.) 7PhysicsDept.,UniversityofNevada,Reno,NV89557,USA;E-Mail: [email protected](R.C.M.) 8FacultyofPhysics,WeizmannInstituteofScience,Rehovot7610001,Israel; E-Mail: [email protected](E.S.) *Authortowhomcorrespondenceshouldbeaddressed;E-Mail: [email protected]; Tel.:+33-49128-8623. Received: 30April2014;inrevisedform: 10June2014/Accepted: 16June2014/ Published: 4July2014 Abstract: Modeling the Stark broadening of spectral lines in plasmas is a complex problem.Theproblemhasalonghistory,sinceitplaysacrucialroleintheinterpretation of the observed spectral lines in laboratories and astrophysical plasmas. One difficulty isthecharacterizationoftheemitter’senvironment. Althoughseveralmodelshavebeen