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Measurements of the L-shell X-ray emission of fluorine-like europium ions ([Eu.sup.54+]) were made under controlled laboratory conditions on the EBIT-I electron beam ion trap at Livermore using an X-ray calorimeter, extending such measurements to the middle of the rare earth elements. Comparing the calorimeter spectra with atomic data from the flexible atomic code, we have identified and analyzed several prominent n = 3 [right arrow] n = 2 transitions, including one two-electron, one-photon core changing transition and one electric quadrupole transition. We find that the measured energies are typically up to several eV higher than predicted. Key words: X-rays, EBIT, europium, wavelength, L-shell, 1. Introduction L-shell X-ray emission from highly charged ions has been a subject of interest in numerous astrophysical observations and in varied measurements involving laboratory plasma sources, with work spanning [...]

In this work, we provide a detailed and elaborate theoretical study of atomic data along with plasma parameters for Kr XXIV. We have computed energy levels, lifetimes, and wave-function compositions for the lowest 148 fine-structure levels by implementing the multi-configuration Dirac-Fock method with the addition of quantum electrodynamics as well as Breit corrections. We have also given the radiative data among 148 levels for electric dipole (E1) transition, which lie in the extreme ultraviolet range. We have compared our calculated results with NIST and other theoretical results available in the literature and attain a good agreement. Because of the unavailability of sufficient and complete data for higher excited levels for Kr XXIV in the literature, a similar calculation has also been compiled using fully relativistic flexible atomic code (FFAC) to access the credibility and integrity of our results. On the other hand, we have also presented the line intensity ratio and plasma parameters for optically thin plasma, which are not published anywhere in the literature, and we believe that our presented results may be advantageous in plasma modeling and astrophysical and fusion plasma research applications. Key words: energy levels, radiative data, line intensity ratio, electron density, plasma temperature. Nous presentons une etude theorique detaillee et elaboree de donnees atomiques et des parametres du plasma du Kr XXIV. Nous calculons les energies, les temps de vie et les fonctions d'onde des premiers 148 niveaux de structure fine en utilisant une methode multi-configurationnelle de Dirac-Fock, incluant des corrections d'electrodynamique quantique et de Breit. Nous produisons aussi les donnees radiatives des transitions dipolaires electriques (E1) entre les 148 niveaux, qui se retrouvent dans l'ultraviolet extreme. Nous comparons nos resultats avec les donnees du NIST et d'autres sources theoriques disponibles et constatons un bon accord. A cause de la faible disponibilite dans la litterature de donnees suffisantes et completes sur les niveaux hautement excites de Kr XXIV, nous refaisons les calculs en utilisant le flexible atomic code (FAC) pleinement relativiste, afin de verifier la credibilite et l'integrite de nos resultats. D'un autre cote, nous presentons aussi des rapports d'intensite de raies et des parametres du plasma pour un plasma optiquement mince, des resultats qui n'apparaissent nulle part dans la litterature. Nous croyons que nos resultats sont interessants pour les chercheurs en modelisation du plasma, en astrophysique et en plasma de fusion. [Traduit par la Redaction] Mots-cles : niveaux d'energie, donnees radiatives, rapport d'intensite de raies, densite electronique, temperature du plasma. PACS Nos.: 32.70.Cs, 32.10.Fn., 1. Introduction During the last few years, the experimental study and identification of spectral lines has increased the demand for atomic data for highly ionized elements. Therefore, atomic structure calculations [...]

Tungsten will be an important element in nearly all future fusion reactors because of its presence in plasma facing components. This makes tungsten a good candidate for a diagnostic element for ion temperature and toroidal velocity measurement, and it makes understanding tungsten emissions important for tokamak power balance. The effect of tungsten on tokamak plasmas is investigated at the Alcator C-Mod tokamak using VUV, bolometry, and soft X-ray spectroscopy. Tungsten was present in Alcator C-Mod as a plasma facing component and through laser blow-off impurity injection. Quasi-continuum emission previously seen at other tokamaks has been identified. Theoretical predictions are presented of tungsten emission that could be expected in future Alcator C-Mod measurements. Furthermore, spectra of highly charged tungsten ions have been studied at the SuperEBIT electron beam ion trap. This emission could prove useful for spectroscopic diagnostics of future high-temperature fusion reactor plasmas. PACS Nos: 52.55.Fa, 52.50.La, 32.30.Rj Le tungstene sera un important element dans les reacteurs a fusion a venir, a cause de sa presence dans les composants face au plasma. Ceci fait du tungstene un bon candidat comme element de diagnostique pour les mesures de temperature des ions et de la vitesse toroi'dale et rend importante la comprehension des emissions du tungstene pour etudier la balance de puissance des tokamaks. Nous etudions l'effet du tungstene sur un plasma de tokamak dans le tokamak Alcator C-Mod, en utilisant les VUV, la bolometrie et la spectroscopie des rayons-X mous. Le tungstene etait present dans l'Alcator comme composant face au plasma et injection des impuretes par ablation de laser. Nous avons identifie le rayonnement quasi-continuum prealablement vu a d'autres tokamaks. Nous presentons des predictions theoriques sur le rayonnement du tungstene qui devrait apparaitre dans des mesures a venir avec l'Alcator. De plus, nous avons etudie les spectres du tungstene fortement ionise avec le piege ionique a faisceau d'electron SuperEBIT. Ce rayonnement pourrait s'averer utile dans le diagnostique de plasmas de haute temperature dans des reacteurs a fusion a venir. [Traduit par la Redaction], 1. Introduction The successful integration of fusion power plants into the power grid is expected to provide a source of clean energy in the future. Many plasma physics programs around [...]

The utilization of tungsten spectroscopy for diagnostics of magnetically confined fusion plasmas requires the radiative properties of tungsten ions to be accurately known. At the Lawrence Livermore National Laboratory, a program to gather spectroscopic data on tungsten ions has been initiated with the purpose to study spectral signatures and identify candidate fusion plasma diagnostics. In this paper, an overview of recent results from the Livermore WOLFRAM spectroscopy project is presented, which includes experimental investigations at the EBIT-I and SuperEBIT electron beam ion traps. In particular, the spectra of highly charged M- and L-shell tungsten ions have been studied. These investigations cover energy measurements of n = 2 to n = 2, 3 transitions in Ne-like [W.sup.64+] through Li- like [W.sup.71+] ions and soft X-ray measurements of n = 3 to n = 3, 4 transitions in M-shell ions with emphasis on the Ni-like [W.sup.46+] and Si-like [W.sup.60+] through Na-like [W.sup.63+] ions. The measurements are complemented by atomic-structure calculations and spectral modeling using the Flexible Atomic Code (FAC). PACS Nos: 32.30.Rj, 52.70.La, 52.72.+v, 52.25.Vy, 31.15.am L'utilisation de la spectroscopie du tungstene dans les diagnostiques de plasmas de fusion confines magnetiquement exige de connaitre avec precision les proprietes radiatives des ions de tungstene. Au Lawrence Livermore National Laboratory, nous avons demarre un programme pour amasser des donnees spectroscopiques sur les ions de tungstene, afin d'etudier les signatures spectrales et d'identifier les candidats pouvant servir a diagnostiquer les plasmas de fusion. Nous passons ici en revue les recents resultats du projet de spectroscopie WOLFRAM de Livermore, incluant les mesures experimentales avec les pieges ioniques a faisceau d'electrons EBIT-I et SuperEBIT. Nous avons etudie en particulier les spectres des couches L et M d' ions fortement charges. Ces mesures couvrent les transitions n =2an = 2, 3 dans les ions tungstene de type Ne, [W.sup.64+], jusqu'aux ions de type Li, [W.sup.71+], ainsi que les rayons-X mous des transitions de n = 2 vers n = 3,4 dans la couche M, en insistant sur les ions de type Ni, [W.sup.46+] et de type Si, [W.sup.60+], jusqu'au type Na, [W.sup.63+]. Les mesures sont presentees avec des calculs de structure atomique et de modelisation spectrale utilisant le ' Flexible Atomic Code ' (FAC). [Traduit par la Redaction], 1. Introduction The radiative properties of tungsten ions need to be better known to fully take advantage of the opportunities tungsten spectra offer for high-temperature fusion plasma diagnostics. With seventy-five [...]

A visible spectral survey (3675-6744 A) from the Alcator C-Mod tokamak has been performed using a high-resolution visible spectrometer constructed at the Lawrence Livermore National Laboratory. The Alcator C-Mod deuterium plasma is shown to have visible emission from numerous atomic species and low charge state ions including, D I, B II-III, BV, C II--III, N II--III, O II-IV, F II-III, Ne I, Na X, Al II--III, Si I-II, Cl II--III, Ar I-III, Ar X, Ti I and III, Fe I-III, Cu I, and III, Mo I, and W I. Nearly all of the emission is thought to come from the cooler edge of the plasma including the scrape-off layer, outside of the last closed magnetic flux surface. However, there is at least one example, included here, where intrinsic visible emission persists deeper into the plasma. PACS Nos: 39.30.+w, 52.55.--s, 32.30.Rj, 07.60.Rd, 52.70.La Nous avons complete une etude du spectre dans le visible (367,5--674,4 nm) dans le tokamak Alcator C-Mod, en utilisant un spectrometre a haute resolution dans le visible, construit au Lawrence Livermore National Laboratory. Nous montrons que le plasma de deuterium de l'Alcator C-Mod a des emissions dans le visible en provenance de plusieurs sources atomiques et ioniques faiblement ionisees, incluant D I, B II--III, B V, C II--III, N II--III, O II--IV, F II--III, Ne I, Na X, Al II--III, Si I--II, Cl II--III, Ar I--III, Ar X, Ti I et III, Fe I--III, Cu I et III, Mo I et W I. Pratiquement toute Permission semble venir de la partie la plus froide du plasma, incluant la couche d'ecorcage en dehors de la derniere surface fermee du champ magnetique. Cependant, il y au moins un exemple, incluant le present cas, ou l'emission visible intrinseque persiste, meme profondement dans le plasma. [Traduit par la Redaction], 1. Introduction Knowledge of plasma impurities is necessary for understanding and optimizing plasma performance. One must tailor any emission-based diagnostic to the plasma composition. Imaging of the visible emission, in [...]

A flat-field grazing-incidence grating spectrometer has been installed on the MIT Alcator C-MOD tokamak, following the installation of such a spectrometer on the Livermore electron beam ion trap facility and on the National Spherical Torus Experiment at Princeton. The spectrometer employs a variable space grating with an average spacing of 2400 lines/mm and covers the 10-70 Å wavelength band. It is being used to monitor the presence of impurity ions such as boron, oxygen, fluorine, argon, calcium, iron, molybdenum, and tungsten, and to calibrate spectral diagnostics of astrophysical plasmas. The Alcator instrument provides spectral emission data in a density regime that is one to three orders of magnitude higher than that covered by the other two instruments and thus produces complementary data. PACS Nos: 32.30.Rj, 39.30.+w, 31.50.+W Nous avons installe un spectrometre a reseau a incidence rasant avec champ plat a l'Alcator C-MOD du MIT, apres l'installation d'un spectrometre similaire au piege ionique a faisceau electronique de Livermore et au National Spherical Torus Experiment de Princeton. Le spectrometre utilise un reseau spatial variable avec un espacement moyen de 2400 lignes/mm et couvre la bande spectrale de 10 a 70 Å. Il est utilise pour detecter la presence d'ions d'impurete comme le bore, l'oxygene, le fluor, l'argon, le calcium, le fer, le molybdene et le tungstene et pour calibrer les diagnostiques spectraux des plasmas astrophysiques. L'Alcator produit des donnees d'emission spectrale dans un regime de densite qui est d'un a trois ordres de grandeur plus grands que les deux autres instruments et fournit donc des donnees complementaires. [Traduit par la Redaction], 1. Introduction The extreme ultraviolet (EUV) region is rich in emission lines that provide important diagnostic information on plasma conditions. The wavelength region between 10 and 70 Å contains, for [...]

Electron-impact excitation cross sections of the electric dipole-allowed [3s.sup.2] ¹[S.sub.0]-3s3p ¹ [P.sup.0.sub.1] transition in Mg-like argon ([Ar.sup.6+]) are calculated using the configuration-interaction and effective many-body Hamiltonian R-matrix close-coupling methods. The near-threshold electron-impact excitation cross sections computed with the effective many-body Hamiltonian R-matrix close-coupling method are in good agreement with the benchmark experimental results. PACS Nos: 31.15.ag, 31.15.am, 32.30.Jc Nous calculons les sections efficaces d'excitation par bombardement electronique de la transition dipolaire electrique permise [3s.sup.2] ¹[s.sub.0]-3s[3p.sup.1] [p.sup.0.sub.1] dans l'Ar de type Mg ([Ar.sup.6+]), en utilisant une interaction de configuration et des methodes de couplage proche a matrice R avec un Hamiltonien efficace a N corps. Les sections efficaces pres du seuil, calculees via cette matrice R, sont en bon accord avec les valeurs experimentales de reference. [Traduit par la Redaction], 1. Introduction Electron-impact excitation (EIE) processes are among the most important atomic processes in astrophysical and laboratory plasmas, for which a number of benchmark laboratory measurements on selected atomic ions [...]

Abstract: High-resolution soft X-ray observations of Ni- and Co-like Xe ions in an electron-beam ion trap are compared with the predictions of various calculations. Calculated energy levels up to the [...]

Abstract: Charge state distributions (CSDs) have been determined in low-density (≅[10.sup.12] [cm.sup.-3]) gold plasmas having either a monoenergetic beam ([E.sub.Beam] = 2.66, 3.53, 4.54, 5.35, 5.85, and 6.35 keV) or [...]

Abstract: The paper reviews the results from tokamak experiments and measurements on electron beam ion traps for the line ratios x/w, y/w, and z/w in the spectra of helium-like ions [...]

Abstract: The past decade has seen a surge of interest in astrophysical charge exchange (CX). The impetus was the discovery of X-ray emission from comets in 1996, soon followed by [...]

Abstract: Multiple spectrometers originally designed for and used at the University of California Lawrence Livermore National Laboratory's electron beam ion trap have found use at various magnetically confined plasma facilities. [...]

Objective: Concurrent dependence on alcohol is common among those seeking treatment for cocaine dependence. More information is needed about differences between those with and without concurrent alcohol dependence, including possible special treatment needs or outcome differences. Method: Data were obtained from 302 adults (70% men) enrolled in outpatient treatment for cocaine dependence. Individuals who did and those who did not meet criteria for alcohol dependence were compared on demographics, drug use, treatment outcome and other variables. Results: With regard to cocaine use, alcoholics were more likely than nonalcoholics to report an intranasal route of administration, use of cocaine in social settings, more simultaneous use of cocaine and alcohol, and more adverse consequences of their cocaine use. With regard to alcohol use, alcoholics reported consuming alcohol more frequently and in larger amounts, had longer drinking histories and were more likely than nonalcoholics to report increases in alcohol consumption when using cocaine. Alcoholics were heavier cigarette smokers than nonalcoholics and reported more severe employment, legal, family and psychiatric problems. There were overall improvements in both groups from intake through 12 months after treatment. With regard to treatment retention and cocaine abstinence, alcoholics had better outcomes than nonalcoholics when treated with intensive behavioral counseling plus incentives, but the reverse was true when treated with control treatments. Conclusions: Compared with nonalcoholic cocaine-dependent subjects, codependent patients exhibit a wider array of problems, many of which merit professional attention. Both alcoholics and nonalcoholics exhibit substantial improvements during treatment, with alcoholics perhaps requiring extra treatment efforts for successful outcomes. (J. Stud. Alcohol 62: 14-22, 2001), MULTIPLE SUBSTANCE USE, especially that involving alcohol abuse and/or dependence, is a well-established characteristic of cocaine-dependent individuals. Results from the Epidemiological Catchment Area study indicate a higher degree of association [...]

Ref.: Can. J. Phys, 89: 615-626 (2011). In the above paper, one of the authors was omitted during the publication process. The correct authors are published here, including the affiliation [...]