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Sheikh UA, Simons L, Duval BP, Février O, Moret D, Allegrucci A, Bernert M, Crisinel F, Tersztyánszky T, Villinger O. RADCAM-A radiation camera system combining foil bolometers, AXUV diodes, and filtered soft x-ray diodes. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:113513. [PMID: 36461455 DOI: 10.1063/5.0095907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 09/29/2022] [Indexed: 06/17/2023]
Abstract
Measurements of radiated power are critical for characterizing and optimizing tokamak performance. The RADCAM system, comprising arrays of foil bolometers, Absolute eXtreme UltraViolet (AXUV), and filtered soft x-ray diodes, has been constructed to provide improved measurements of plasma radiation on "Tokamak a Configuration Variable" (TCV). An overview of the physical geometry, electronics, and design of the system is provided. The construction of the bolometer foils together with the improved sensitivity characteristics resulting from the inclusion of an anti-reflection carbon coating are presented. The large number of lines of sight in RADCAM are shown to significantly increase the spatial resolution over the legacy system. The system calibration procedure is detailed, and the mean system sensitivity is shown to vary by less than 5% over 1000 discharges. Additionally, the methodology for cross-calibration of the AXUV diodes with the bolometer foils is presented and applied to generate high temporal resolution measurements. The RADCAM radiation camera system is a compact, versatile system that is demonstrated to provide high resolution profiles of the radiated power in TCV.
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Affiliation(s)
- U A Sheikh
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - L Simons
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - B P Duval
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - O Février
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - D Moret
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - A Allegrucci
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - M Bernert
- Max Planck Institute für Plasmaphysik, Boltzmannstr. 2, 85748 Garching, Germany
| | - F Crisinel
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - T Tersztyánszky
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - O Villinger
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
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2
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Dai LL, Zhu YB, Bai RH, Li Q, Tao RY, Liu LC, Ding JB, Ma F, Zhao X, Cheng SK, Huang XL, Liu MS. Time resolved absolute extreme ultraviolet radiation measurement on the ENN XuanLong-50 spherical tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:083507. [PMID: 34470401 DOI: 10.1063/5.0040648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
A plasma radiation measurement system for a wide spectral range, based on compact Absolute eXtreme UltraViolet (AXUV) silicon photodiodes, has been implemented on the newly constructed ENN XuanLong-50 (EXL-50) spherical tokamak. The system consists of two 16-channel AXUV16ELG arrays and one AXUV63HS1 single-cell detector mounted on ceramic sockets. The two arrays, facing toward the EXL-50 slim central post from two locations inside a top and a side ConFlat 400 port, have 32 view chords covering the interested plasma region in a poloidal cross section at toroidal 330°. The single-cell detector, seated on a retractable feedthrough, could be arranged flexibly with the help of an ultra-high vacuum compatible gate valve. The design details together with considerations on the EXL-50 specific engineering realities and physics requirements are described. Preliminary results from the EXL-50 2020 experimental campaign are presented.
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Affiliation(s)
- L L Dai
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - Y B Zhu
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - R H Bai
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - Q Li
- Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China
| | - R Y Tao
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - L C Liu
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - J B Ding
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - F Ma
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - X Zhao
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - S K Cheng
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - X L Huang
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
| | - M S Liu
- Hebei Key Laboratory of Compact Fusion, Langfang 065001, China
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3
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Reinke ML, Terry JL, van Eden GG, Peterson BJ, Mukai K, Gray TK, Stratton BC. Experimental tests of an infrared video bolometer on Alcator C-Mod. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:103507. [PMID: 30399930 DOI: 10.1063/1.5047050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 09/24/2018] [Indexed: 06/08/2023]
Abstract
A prototype of an infrared imaging bolometer (IRVB) was successfully tested on the Alcator C-Mod tokamak at the end of its 2016 campaign. The IRVB method interprets the power radiated from the plasma by measuring the temperature rise of a thin, ∼2 μm, Pt absorber that is placed in the torus vacuum and exposed, using a pinhole camera, to the full-spectrum of plasma's photon emission. The IRVB installed on C-Mod viewed the poloidal cross section of the core plasma and observed Ohmic and ion cyclotron range of frequency (ICRF)-heated plasmas. Analysis of total radiated power and on-axis emissivity from IRVB is summarized, and quantitative comparisons made to data from both resistive bolometers and AXUV diodes. IRVB results are clearly within a factor of two, but additional effort is needed for it to be used to fully support power exhaust research. The IRVB is shown to be immune to electromagnetic interference from ICRF which strongly impacts C-Mod's resistive bolometers. Results of the bench-top calibration are summarized, including a novel temperature calibration method useful for IRVBs.
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Affiliation(s)
- M L Reinke
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830-6286, USA
| | - J L Terry
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - G G van Eden
- Dutch Institute for Fusion Energy, Eindhoven, The Netherlands
| | - B J Peterson
- National Institute for Fusion Science, Toki, Japan
| | - K Mukai
- National Institute for Fusion Science, Toki, Japan
| | - T K Gray
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830-6286, USA
| | - B C Stratton
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
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4
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Diagnostics, data acquisition and control of the divertor test tokamak experiment. FUSION ENGINEERING AND DESIGN 2017. [DOI: 10.1016/j.fusengdes.2017.05.118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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5
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van Eden GG, Reinke ML, Peterson BJ, Gray TK, Delgado-Aparicio LF, Jaworski MA, Lore J, Mukai K, Sano R, Pandya SN, Morgan TW. Design and characterization of a prototype divertor viewing infrared video bolometer for NSTX-U. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:11D402. [PMID: 27910411 DOI: 10.1063/1.4955487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The InfraRed Video Bolometer (IRVB) is a powerful tool to measure radiated power in magnetically confined plasmas due to its ability to obtain 2D images of plasma emission using a technique that is compatible with the fusion nuclear environment. A prototype IRVB has been developed and installed on NSTX-U to view the lower divertor. The IRVB is a pinhole camera which images radiation from the plasma onto a 2.5 μm thick, 9 × 7 cm2 Pt foil and monitors the resulting spatio-temporal temperature evolution using an IR camera. The power flux incident on the foil is calculated by solving the 2D+time heat diffusion equation, using the foil's calibrated thermal properties. An optimized, high frame rate IRVB, is quantitatively compared to results from a resistive bolometer on the bench using a modulated 405 nm laser beam with variable power density and square wave modulation from 0.2 Hz to 250 Hz. The design of the NSTX-U system and benchtop characterization are presented where signal-to-noise ratios are assessed using three different IR cameras: FLIR A655sc, FLIR A6751sc, and SBF-161. The sensitivity of the IRVB equipped with the SBF-161 camera is found to be high enough to measure radiation features in the NSTX-U lower divertor as estimated using SOLPS modeling. The optimized IRVB has a frame rate up to 50 Hz, high enough to distinguish radiation during edge-localized-modes (ELMs) from that between ELMs.
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Affiliation(s)
- G G van Eden
- Dutch Institute for Fundamental Energy Research, 5612 AJ Eindhoven, The Netherlands
| | - M L Reinke
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - B J Peterson
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - T K Gray
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - L F Delgado-Aparicio
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
| | - M A Jaworski
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
| | - J Lore
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - K Mukai
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - R Sano
- National Institutes for Quantum and Radiological Science and Technology, Naka 311-0193, Japan
| | - S N Pandya
- Institute for Plasma Research, Bhat Village, Gandhinagar, 382428 Gujarat, India
| | - T W Morgan
- Dutch Institute for Fundamental Energy Research, 5612 AJ Eindhoven, The Netherlands
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Delgado-Aparicio L, Bell RE, Faust I, Tritz K, Diallo A, Gerhardt SP, Kozub TA, LeBlanc BP, Stratton BC. High-resolution tangential absolute extreme ultraviolet arrays for radiated power density measurements on NSTX-U. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11D859. [PMID: 25430272 DOI: 10.1063/1.4894835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The radiated-power-density diagnostic on the equatorial midplane for the NSTX-U tokamak will be upgraded to measure the radial structure of the photon emissivity profile with an improved radial resolution. This diagnostic will enhance the characterization and studies of power balance, impurity transport, and MHD. The layout and response expected of the new system is shown for different plasma conditions and impurity concentrations. The effect of toroidal rotation driving poloidal asymmetries in the core radiation from high-Z impurities is also addressed.
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Affiliation(s)
| | - R E Bell
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - I Faust
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - K Tritz
- The Johns Hopkins University, Baltimore, Maryland 21209, USA
| | - A Diallo
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - S P Gerhardt
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - T A Kozub
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - B P LeBlanc
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - B C Stratton
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
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Bernert M, Eich T, Burckhart A, Fuchs JC, Giannone L, Kallenbach A, McDermott RM, Sieglin B. Application of AXUV diode detectors at ASDEX Upgrade. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:033503. [PMID: 24689581 DOI: 10.1063/1.4867662] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the ASDEX Upgrade tokamak, a radiation measurement for a wide spectral range, based on semiconductor detectors, with 256 lines of sight and a time resolution of 5 μs was recently installed. In combination with the foil based bolometry, it is now possible to estimate the absolutely calibrated radiated power of the plasma on fast timescales. This work introduces this diagnostic based on AXUV (Absolute eXtended UltraViolet) n-on-p diodes made by International Radiation Detectors, Inc. The measurement and the degradation of the diodes in a tokamak environment is shown. Even though the AXUV diodes are developed to have a constant sensitivity for all photon energies (1 eV-8 keV), degradation leads to a photon energy dependence of the sensitivity. The foil bolometry, which is restricted to a time resolution of less than 1 kHz, offers a basis for a time dependent calibration of the diodes. The measurements of the quasi-calibrated diodes are compared with the foil bolometry and found to be accurate on the kHz time scale. Therefore, it is assumed, that the corrected values are also valid for the highest time resolution (200 kHz). With this improved diagnostic setup, the radiation induced by edge localized modes is analyzed on fast timescales.
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Affiliation(s)
- M Bernert
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
| | - T Eich
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
| | - A Burckhart
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
| | - J C Fuchs
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
| | - L Giannone
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
| | - A Kallenbach
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
| | - R M McDermott
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
| | - B Sieglin
- Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany
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8
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Tal B, Labit B, Nagy D, Chavan R, Duval B, Veres G. Plasma radiation dynamics with the upgraded Absolute Extreme Ultraviolet tomographical system in the Tokamak à Configuration Variable. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:123508. [PMID: 24387434 DOI: 10.1063/1.4848155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We introduce an upgraded version of a tomographical system which is built up from Absolute Extreme Ultraviolet-type (AXUV) detectors and has been installed on the Tokamak à Configuration Variable (TCV). The system is suitable for the investigation of fast radiative processes usually observed in magnetically confined high-temperature plasmas. The upgrade consists in the detector protection by movable shutters, some modifications to correct original design errors and the improvement in the data evaluation techniques. The short-term sensitivity degradation of the detectors, which is caused by the plasma radiation itself, has been monitored and found to be severe. The results provided by the system are consistent with the measurements obtained with the usual plasma radiation diagnostics installed on TCV. Additionally, the coupling between core plasma radiation and plasma-wall interaction is revealed. This was impossible with other available diagnostics on TCV.
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Affiliation(s)
- B Tal
- Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Association EURATOM, P. O. Box 49, H-1525 Budapest, Hungary
| | - B Labit
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, EPFL SB CRPP, Station 13, CH-1015 Lausanne, Switzerland
| | - D Nagy
- Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Association EURATOM, P. O. Box 49, H-1525 Budapest, Hungary
| | - R Chavan
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, EPFL SB CRPP, Station 13, CH-1015 Lausanne, Switzerland
| | - B Duval
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, EPFL SB CRPP, Station 13, CH-1015 Lausanne, Switzerland
| | - G Veres
- Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Association EURATOM, P. O. Box 49, H-1525 Budapest, Hungary
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Delgado-Aparicio L, Sugiyama L, Granetz R, Gates DA, Rice JE, Reinke ML, Bitter M, Fredrickson E, Gao C, Greenwald M, Hill K, Hubbard A, Hughes JW, Marmar E, Pablant N, Podpaly Y, Scott S, Wilson R, Wolfe S, Wukitch S. Formation and stability of impurity "snakes" in tokamak plasmas. PHYSICAL REVIEW LETTERS 2013; 110:065006. [PMID: 23432265 DOI: 10.1103/physrevlett.110.065006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Indexed: 06/01/2023]
Abstract
New observations of the formation and dynamics of long-lived impurity-induced helical "snake" modes in tokamak plasmas have recently been carried out on Alcator C-Mod. The snakes form as an asymmetry in the impurity ion density that undergoes a seamless transition from a small helically displaced density to a large crescent-shaped helical structure inside q<1, with a regularly sawtoothing core. The observations show that the conditions for the formation and persistence of a snake cannot be explained by plasma pressure alone. Instead, many features arise naturally from nonlinear interactions in a 3D MHD model that separately evolves the plasma density and temperature.
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Delgado-Aparicio L, Bitter M, Granetz R, Reinke M, Beiersdorfer P, Gates D, Hill K, Pablant N, Podpaly Y, Rice J, Sugiyama L. Molybdenum emission from impurity-induced m = 1 snake-modes on the Alcator C-Mod tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:10E517. [PMID: 23127024 DOI: 10.1063/1.4733731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A suite of novel high-resolution spectroscopic imaging diagnostics has facilitated the identification and localization of molybdenum impurities as the main species during the formation and lifetime of m = 1 impurity-induced snake-modes on Alcator C-Mod. Such measurements made it possible to infer, for the first time, the perturbed radiated power density profiles from which the impurity density can be deduced.
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Soukhanovskii VA, Roquemore AL, Bell RE, Kaita R, Kugel HW. Spectroscopic diagnostics for liquid lithium divertor studies on National Spherical Torus Experiment. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D723. [PMID: 21033916 DOI: 10.1063/1.3478749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The use of lithium-coated plasma facing components for plasma density control is studied in the National Spherical Torus Experiment (NSTX). A recently installed liquid lithium divertor (LLD) module has a porous molybdenum surface, separated by a stainless steel liner from a heated copper substrate. Lithium is deposited on the LLD from two evaporators. Two new spectroscopic diagnostics are installed to study the plasma surface interactions on the LLD: (1) A 20-element absolute extreme ultraviolet (AXUV) diode array with a 6 nm bandpass filter centered at 121.6 nm (the Lyman-α transition) for spatially resolved divertor recycling rate measurements in the highly reflective LLD environment, and (2) an ultraviolet-visible-near infrared R=0.67 m imaging Czerny-Turner spectrometer for spatially resolved divertor D I, Li I-II, C I-IV, Mo I, D(2), LiD, CD emission and ion temperature on and around the LLD module. The use of photometrically calibrated measurements together with atomic physics factors enables studies of recycling and impurity particle fluxes as functions of LLD temperature, ion flux, and divertor geometry.
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Affiliation(s)
- V A Soukhanovskii
- Lawrence Livermore National Laboratory, Livermore, California 94551, USA.
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