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Galdon-Quiroga J, Birkenmeier G, Oyola P, Lindl H, Rodriguez-Gonzalez A, Anda G, Garcia-Munoz M, Herrmann A, Kalis J, Kaunert K, Lunt T, Refy D, Rohde V, Rueda-Rueda J, Sochor M, Tal B, Teschke M, Videla M, Viezzer E, Zoletnik S. First measurements of an imaging heavy ion beam probe at the ASDEX Upgrade tokamak. Rev Sci Instrum 2024; 95:013504. [PMID: 38206100 DOI: 10.1063/5.0175720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024]
Abstract
The imaging heavy ion beam probe (i-HIBP) diagnostic has been successfully commissioned at ASDEX Upgrade. The i-HIBP injects a primary neutral beam into the plasma, where it is ionized, leading to a fan of secondary (charged) beams. These are deflected by the magnetic field of the tokamak and collected by a scintillator detector, generating a strike-line light pattern that encodes information on the density, electrostatic potential, and magnetic field of the plasma edge. The first measurements have been made, demonstrating the proof-of-principle of this diagnostic technique. A primary beam of 85/87Rb has been used with energies ranging between 60 and 72 keV and extracted currents up to 1.5 mA. The first signals have been obtained in experiments covering a wide range of parameter spaces, with plasma currents (Ip) between 0.2 and 0.8 MA and on-axis toroidal magnetic field (Bt) between 1.9 and 2.7 T. Low densities appear to be critical for the performance of the diagnostic, as signals are typically observed only when the line integrated density is below 2.0-3.0 × 1019 m-2 in the central interferometer chord, depending on the plasma shape. The strike line moves as expected when Ip is ramped, indicating that current measurements are possible. Additionally, clear dynamics in the intensity of the strike line are often observed, which might be linked to changes in the edge profile structure. However, the signal-to-background ratio of the signals is hampered by stray light, and the image guide degradation is due to neutron irradiation. Finally, simulations have been carried out to investigate the sensitivity of the expected signals to plasma density and temperature. The results are in qualitative agreement with the experimental observations, suggesting that the diagnostic is almost insensitive to fluctuations in the temperature profile, while the signal level is highly determined by the density profile due to the beam attenuation.
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Affiliation(s)
- J Galdon-Quiroga
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain
| | - G Birkenmeier
- Max Planck Institute for Plasma Physics, Garching, Germany
- TUM School of Natural Sciences, Physics Department, Technical University of Munich, 85748 Garching, Germany
| | - P Oyola
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain
| | - H Lindl
- Max Planck Institute for Plasma Physics, Garching, Germany
- TUM School of Natural Sciences, Physics Department, Technical University of Munich, 85748 Garching, Germany
| | - A Rodriguez-Gonzalez
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain
| | - G Anda
- Centre for Energy Research, Budapest, Hungary
| | - M Garcia-Munoz
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain
| | - A Herrmann
- Max Planck Institute for Plasma Physics, Garching, Germany
| | - J Kalis
- Max Planck Institute for Plasma Physics, Garching, Germany
- TUM School of Natural Sciences, Physics Department, Technical University of Munich, 85748 Garching, Germany
| | - K Kaunert
- Max Planck Institute for Plasma Physics, Garching, Germany
| | - T Lunt
- Max Planck Institute for Plasma Physics, Garching, Germany
| | - D Refy
- Centre for Energy Research, Budapest, Hungary
| | - V Rohde
- Max Planck Institute for Plasma Physics, Garching, Germany
| | - J Rueda-Rueda
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain
| | - M Sochor
- Max Planck Institute for Plasma Physics, Garching, Germany
| | - B Tal
- Max Planck Institute for Plasma Physics, Garching, Germany
| | - M Teschke
- Max Planck Institute for Plasma Physics, Garching, Germany
| | - M Videla
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain
| | - E Viezzer
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain
| | - S Zoletnik
- Centre for Energy Research, Budapest, Hungary
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2
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Balazs P, Asztalos O, Anda G, Vecsei M, Zoletnik S, Kumar S, Pokol G. Special behavior of alkali beam emission spectroscopy in low-ion-temperature plasma. Fusion Engineering and Design 2023. [DOI: 10.1016/j.fusengdes.2023.113650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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3
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Szepesi T, Bartók G, Cseh G, Gárdonyi G, Jachmich S, Katona I, Kocsis G, Oravecz D, Walcz E, Zoletnik S. In-situ pellet growth and quality monitoring diagnostics for the ITER DMS Support Laboratory. Fusion Engineering and Design 2023. [DOI: 10.1016/j.fusengdes.2023.113555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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4
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Zoletnik S, Walcz E, Jachmich S, Kruezi U, Lehnen M, Anda G, Szabolics T, Szepesi T, Bartók G, Cseh G, Boros Z, Dunai D, Gárdonyi G, Hakl J, Hegedűs S, Katona I, Kovacs A, Kocsis G, Lengyel M, Mészáros S, Nagy D, Oravecz D, Poszovecz L, Réfy D, Vad K, Vécsei M. Shattered pellet technology development in the ITER DMS test laboratory. Fusion Engineering and Design 2023. [DOI: 10.1016/j.fusengdes.2023.113701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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5
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Vécsei M, Anda G, Asztalos O, Dunai D, Hegedűs S, Nagy D, Otte M, Pokol GI, Zoletnik S. Swift evaluation of electron density profiles obtained by the alkali beam emission spectroscopy technique using linearized reconstruction. Rev Sci Instrum 2021; 92:113501. [PMID: 34852513 DOI: 10.1063/5.0057158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
A method is presented for the swift reconstruction of electron density profiles measured by the alkali beam emission spectroscopy. It is based on the linearization of the governing rate equations and leads to a direct calculation for obtaining the profiles. The uncertainties of the measurement are incorporated into the problem through the utilization of Tikhonov regularization and the generalized least squares method. An approximation for the uncertainty of the reconstructed density data is calculated as well. The applicability of the method is tested against both simulated and real experimental results of the W7-X stellarator.
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Affiliation(s)
- M Vécsei
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - G Anda
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - O Asztalos
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - D Dunai
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - S Hegedűs
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - D Nagy
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - M Otte
- Max-Planck Institute for Plasma Physics, Wendelsteinstrasse 1, 17491 Greifswald, Germany
| | - G I Pokol
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - S Zoletnik
- Centre for Energy Research, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
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6
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Birkenmeier G, Galdon-Quiroga J, Olevskaia V, Oyola P, Toledo-Garrido J, Bald K, Sochor M, Anda G, Zoletnik S, Herrmann A, Rohde V, Teschke M, Giannone L, Lunt T, Viezzer E, Garcia-Munoz M, team TASDEXU. Hardware developments and commissioning of the imaging heavy ion beam probe at ASDEX upgrade. Fusion Engineering and Design 2021. [DOI: 10.1016/j.fusengdes.2021.112644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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7
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Gonzalez-Martin J, Garcia-Munoz M, Sieglin B, Herrmann A, Lunt T, Ayllon-Guerola J, Galdon-Quiroga J, Hidalgo-Salaverri J, Kovacsik A, Rivero-Rodriguez JF, Sanchis L, Silvagni D, Zoletnik S, Dominguez J. Self-adaptive diagnostic of radial fast-ion loss measurements on the ASDEX Upgrade tokamak (invited). Rev Sci Instrum 2021; 92:053538. [PMID: 34243326 DOI: 10.1063/5.0043756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 04/28/2021] [Indexed: 06/13/2023]
Abstract
A poloidal array of scintillator-based Fast-Ion Loss Detectors (FILDs) has been installed in the ASDEX Upgrade (AUG) tokamak. While all AUG FILD systems are mounted on reciprocating arms driven externally by servomotors, the reciprocating system of the FILD probe located just below the midplane is based on a magnetic coil that is energized in real-time by the AUG discharge control system. This novel reciprocating system allows, for the first time, real-time control of the FILD position including infrared measurements of its probe head temperature to avoid overheating. This considerably expands the diagnostic operational window, enabling unprecedented radial measurements of fast-ion losses. Fast collimator-slit sweeping (up to 0.2 mm/ms) is used to obtain radially resolved velocity-space measurements along 8 cm within the scrape-off layer. This provides a direct evaluation of the neutral beam deposition profiles via first-orbit losses. Moreover, the light-ion beam probe (LIBP) technique is used to infer radial profiles of fast-ion orbit deflection. This radial-LIBP technique is applied to trapped orbits (exploring both the plasma core and the FILD stroke near the wall), enabling radial localization of internal plasma fluctuations (neoclassical tearing modes). This is quantitatively compared against electron cyclotron emission measurements, showing excellent agreement. For the first time, radial profiles of fast-ion losses in MHD quiescent plasmas as well as in the presence of magnetic islands and edge localized modes are presented.
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Affiliation(s)
- J Gonzalez-Martin
- Department of Mechanical Engineering and Manufacturing, Universidad de Sevilla, 41092 Sevilla, Spain
| | - M Garcia-Munoz
- Centro Nacional de Aceleradores (CNA), 41092 Sevilla, Spain
| | - B Sieglin
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - A Herrmann
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - T Lunt
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - J Ayllon-Guerola
- Department of Mechanical Engineering and Manufacturing, Universidad de Sevilla, 41092 Sevilla, Spain
| | - J Galdon-Quiroga
- Department of Atomic, Molecular and Nuclear Physics, Universidad de Sevilla, 41012 Sevilla, Spain
| | - J Hidalgo-Salaverri
- Department of Mechanical Engineering and Manufacturing, Universidad de Sevilla, 41092 Sevilla, Spain
| | - A Kovacsik
- Budapest University of Technology and Economics, 1111 Budapest, Hungary
| | - J F Rivero-Rodriguez
- Department of Mechanical Engineering and Manufacturing, Universidad de Sevilla, 41092 Sevilla, Spain
| | - L Sanchis
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | - D Silvagni
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | | | - J Dominguez
- Department of Mechanical Engineering and Manufacturing, Universidad de Sevilla, 41092 Sevilla, Spain
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8
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Réfy DI, Zoletnik S, Dunai D, Anda G, Lampert M, Hegedűs S, Nagy D, Palánkai M, Kádi J, Leskó B, Aradi M, Hacek P, Weinzettl V. Micro-Faraday cup matrix detector for ion beam measurements in fusion plasmas. Rev Sci Instrum 2019; 90:033501. [PMID: 30927772 DOI: 10.1063/1.5084219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/11/2019] [Indexed: 06/09/2023]
Abstract
Atomic beam probe is an extension of the routinely used beam emission spectroscopy diagnostic for the plasma edge current fluctuation measurement at magnetically confined plasmas. Beam atoms ionized by the plasma are directed to a curved trajectory by the magnetic field and may be detected close to the wall of the device. The arrival location and current distribution of the ions carry information about the plasma current distribution, the density profile, and the electric potential in the plasma edge. This paper describes a micro-Faraday cup matrix detector for the measurement of the few microampere ion current distribution close to the plasma edge. The device implements a shallow Faraday cup matrix, produced by printed-circuit board technology. Secondary electrons induced by the plasma radiation and the ion bombardment are basically confined into the cups by the tokamak magnetic field. Additionally, a double mask is installed in the front face to limit the ion influx into the cups and supplement secondary electron suppression. The setup was tested in detail using a lithium ion beam in the laboratory. Switching time, cross talk, and fluctuation sensitivity test results in the lab setup are presented along with the detector setup to be installed at the COMPASS tokamak.
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Affiliation(s)
- D I Réfy
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - S Zoletnik
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - D Dunai
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - G Anda
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - M Lampert
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - S Hegedűs
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - D Nagy
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - M Palánkai
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - J Kádi
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - B Leskó
- Plasma Physics Department, Wigner Research Centre for Physics, XII. Konkoly Thege Miklós út 29-33, 1121 Budapest, Hungary
| | - M Aradi
- Fusion@ÖAW, Institute of Theoretical and Computational Physics, Graz University of Technology, Petersgasse 16, A8010 Graz, Austria
| | - P Hacek
- Tokamak Department, Institute of Plasma Physics of the CAS, 182 00 Prague, Czech Republic
| | - V Weinzettl
- Tokamak Department, Institute of Plasma Physics of the CAS, 182 00 Prague, Czech Republic
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9
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Hathiramani D, Ali A, Anda G, Barbui T, Biedermann C, Charl A, Chauvin D, Czymek G, Dhard C, Drewelow P, Dudek A, Effenberg F, Ehrke G, Endler M, Ennis D, Fellinger J, Ford O, Freundt S, Gradic D, Grosser K, Harris J, Hölbe H, Jakubowski M, Knaup M, Kocsis G, König R, Krause M, Kremeyer T, Kornejew P, Krychowiak M, Lambertz H, Jenzsch H, Mayer M, Mohr S, Neubauer O, Otte M, Perseo V, Pilopp D, Rudischhauser L, Schmitz O, Schweer B, Schülke M, Stephey L, Szepesi T, Terra A, Toth M, Wenzel U, Wurden G, Zoletnik S, Pedersen TS. Upgrades of edge, divertor and scrape-off layer diagnostics of W7‐X for OP1.2. Fusion Engineering and Design 2018. [DOI: 10.1016/j.fusengdes.2018.02.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Hacek P, Berta M, Anda G, Aradi M, Bencze A, Dunai D, Krbec J, Panek R, Refy DI, Stockel J, Weinzettl V, Zoletnik S. Development of an ion beam detector for the atomic beam probe diagnostic. Rev Sci Instrum 2018; 89:113506. [PMID: 30501297 DOI: 10.1063/1.5044529] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 10/29/2018] [Indexed: 06/09/2023]
Abstract
The atomic beam probe diagnostic concept aims at measuring the edge magnetic field and through that edge current distribution in fusion plasmas by observing trajectories of an ion beam stemming from a diagnostic neutral beam. The diagnostic potentially has microsecond scale time resolution and can thus prove to be a powerful option to study fast changes in the edge plasma. A test detector has been installed on the COMPASS tokamak as an extension of the existing lithium beam diagnostic system. It employs a relatively simple concept of an array of conductive detection plates measuring the incident ion current, which is then amplified and converted to a voltage signal. The aim of the test detector is to experimentally examine the idea of the diagnostic and provide background data for design and installation of a final detector. Also, a numerical code based on the CUDA parallel computing platform has been developed for modeling lithium ion trajectories in the given COMPASS plasma discharges. We present the developments of the detector design and test measurements of the diagnostic performed both in a laboratory beam system and on the COMPASS tokamak.
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Affiliation(s)
- P Hacek
- Institute of Plasma Physics of the Czech Academy of Sciences, Prague, Czech Republic
| | - M Berta
- Institute of Plasma Physics of the Czech Academy of Sciences, Prague, Czech Republic
| | - G Anda
- Wigner RCP, Budapest, Hungary
| | - M Aradi
- Graz University of Technology, Graz, Austria
| | | | - D Dunai
- Wigner RCP, Budapest, Hungary
| | - J Krbec
- Institute of Plasma Physics of the Czech Academy of Sciences, Prague, Czech Republic
| | - R Panek
- Institute of Plasma Physics of the Czech Academy of Sciences, Prague, Czech Republic
| | | | - J Stockel
- Institute of Plasma Physics of the Czech Academy of Sciences, Prague, Czech Republic
| | - V Weinzettl
- Institute of Plasma Physics of the Czech Academy of Sciences, Prague, Czech Republic
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11
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Gonzalez-Martin J, Ayllon-Guerola J, Garcia-Munoz M, Herrmann A, Leitenstern P, De Marne P, Zoletnik S, Kovacsik A, Galdon-Quiroga J, Rivero-Rodriguez J, Rodriguez-Ramos M, Sanchis-Sanchez L, Dominguez J. First measurements of a scintillator based fast-ion loss detector near the ASDEX Upgrade divertor. Rev Sci Instrum 2018; 89:10I106. [PMID: 30399966 DOI: 10.1063/1.5038968] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 06/03/2018] [Indexed: 06/08/2023]
Abstract
A new reciprocating scintillator based fast-ion loss detector has been installed a few centimeters above the outer divertor of the ASDEX Upgrade tokamak and between two of its lower Edge Localized Modes (ELM) mitigation coils. The detector head containing the scintillator screen, Faraday cup, calibration lamp, and collimator systems are installed on a motorized reciprocating system that can adjust its position via remote control in between plasma discharges. Orbit simulations are used to optimize the detector geometry and velocity-space coverage. The scintillator image is transferred to the light acquisition systems outside of the vacuum via a lens relay (embedded in a 3D-printed titanium holder) and an in-vacuum image guide. A charge coupled device camera, for high velocity-space resolution, and an 8 × 8 channel avalanche photo diode camera, for high temporal resolution (up to 2 MHz), are used as light acquisition systems. Initial results showing velocity-space of neutral beam injection prompt losses and fast-ion losses induced by a (2, 1) neoclassical tearing mode are presented.
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Affiliation(s)
- J Gonzalez-Martin
- Department of Mechanical and Manufacturing Engineering, University of Seville, C/Camino de los Descubrimientos s/n, Isla de la Cartuja, Seville, Spain
| | - J Ayllon-Guerola
- Department of Mechanical and Manufacturing Engineering, University of Seville, C/Camino de los Descubrimientos s/n, Isla de la Cartuja, Seville, Spain
| | | | - A Herrmann
- Max-Planck-Institut für Plasmaphysik, Garching, Germany
| | - P Leitenstern
- Max-Planck-Institut für Plasmaphysik, Garching, Germany
| | - P De Marne
- Max-Planck-Institut für Plasmaphysik, Garching, Germany
| | | | | | | | - J Rivero-Rodriguez
- Department of Mechanical and Manufacturing Engineering, University of Seville, C/Camino de los Descubrimientos s/n, Isla de la Cartuja, Seville, Spain
| | | | | | - J Dominguez
- Department of Mechanical and Manufacturing Engineering, University of Seville, C/Camino de los Descubrimientos s/n, Isla de la Cartuja, Seville, Spain
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12
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Zoletnik S, Anda G, Aradi M, Asztalos O, Bató S, Bencze A, Berta M, Demeter G, Dunai D, Hacek P, Hegedűs S, Hu GH, Krizsanóczi T, Lampert M, Nagy D, Németh J, Otte M, Petravich G, Pokol GI, Réfy D, Tál B, Vécsei M. Advanced neutral alkali beam diagnostics for applications in fusion research (invited). Rev Sci Instrum 2018; 89:10D107. [PMID: 30399868 DOI: 10.1063/1.5039309] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 06/15/2018] [Indexed: 06/08/2023]
Abstract
Diagnosing the density profile at the edge of high temperature fusion plasmas by an accelerated lithium beam is a known technique since decades. By knowledge of the relevant atomic physics rate coefficients, the plasma electron density profile can be calculated from the relatively calibrated light profile along the beam. Several additional possibilities have already been demonstrated: Charge Exchange Resonance Spectroscopy (CXRS) for ion temperature/flow and Zeeman polarimetry for edge plasma current; therefore the Li-beam diagnostic offers a wealth of information at the plasma edge. The weaknesses of the method are the relatively faint light signal, background light, and technical difficulties of the beam injector which usually seriously limit the applicability. In this talk, we present systematic developments in alkali-beam diagnostics (Li, Na) for the injector and the observation system and detectors which resulted in strongly increased capabilities. Advanced systems have been built, and microsecond scale density profile, turbulence, and zonal flow measurement have been demonstrated. A novel edge current measurement technique has also been designed, and components have been tested with potential microsecond-scale time resolution. Additional possibilities of these advanced systems for spectral measurements (CXRS and various Zeeman schemes) are also discussed.
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Affiliation(s)
- S Zoletnik
- Wigner Research Centre for Physics, Budapest, Hungary
| | - G Anda
- Wigner Research Centre for Physics, Budapest, Hungary
| | - M Aradi
- Graz University of Technology, Graz, Austria
| | - O Asztalos
- Budapest University of Technology and Economics, Budapest, Hungary
| | - S Bató
- Wigner Research Centre for Physics, Budapest, Hungary
| | - A Bencze
- Wigner Research Centre for Physics, Budapest, Hungary
| | - M Berta
- Széchenyi University, Győr, Hungary
| | - G Demeter
- Wigner Research Centre for Physics, Budapest, Hungary
| | - D Dunai
- Wigner Research Centre for Physics, Budapest, Hungary
| | - P Hacek
- Institute for Plasma Physics, Czech Academy of Sciences, Prague, Czech Republic
| | - S Hegedűs
- Wigner Research Centre for Physics, Budapest, Hungary
| | - G H Hu
- Institute for Plasma Physics, Chinese Academy of Sciences, Hefei, China
| | - T Krizsanóczi
- Wigner Research Centre for Physics, Budapest, Hungary
| | - M Lampert
- Wigner Research Centre for Physics, Budapest, Hungary
| | - D Nagy
- Wigner Research Centre for Physics, Budapest, Hungary
| | - J Németh
- Wigner Research Centre for Physics, Budapest, Hungary
| | - M Otte
- Max Planck Institute for Plasma Physics, Greifswald, Germany
| | - G Petravich
- Wigner Research Centre for Physics, Budapest, Hungary
| | - G I Pokol
- Budapest University of Technology and Economics, Budapest, Hungary
| | - D Réfy
- Wigner Research Centre for Physics, Budapest, Hungary
| | - B Tál
- Wigner Research Centre for Physics, Budapest, Hungary
| | - M Vécsei
- Wigner Research Centre for Physics, Budapest, Hungary
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13
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Zoletnik S, Hu GH, Tál B, Dunai D, Anda G, Asztalos O, Pokol GI, Kálvin S, Németh J, Krizsanóczi T. Ultrafast two-dimensional lithium beam emission spectroscopy diagnostic on the EAST tokamak. Rev Sci Instrum 2018; 89:063503. [PMID: 29960560 DOI: 10.1063/1.5017224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A diagnostic instrument is described for the Experimental Advanced Superconducting Tokamak (EAST) for the measurement of the edge plasma electron density profile and plasma turbulence properties. An accelerated neutral lithium beam is injected into the tokamak and the Doppler shifted 670.8 nm light emission of the Li2p-2s transition is detected. A novel compact setup is used, where the beam injection and observation take place from the same equatorial diagnostic port and radial-poloidal resolution is achieved with microsecond time resolution. The observation direction is optimized in order to achieve a sufficient Doppler shift of the beam light to be able to separate from the strong edge lithium line emission on this lithium coated device. A 250 kHz beam chopping technique is also demonstrated for the removal of background light. First results show the capability of measuring turbulence and its poloidal flow velocity in the scrape-off layer and edge region and the resolution of details of transient phenomena like edge localized modes with few microsecond time resolution.
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Affiliation(s)
- S Zoletnik
- Wigner Research Centre for Physics, Budapest, Hungary
| | - G H Hu
- Institute for Plasma Physics, Chinese Academy of Sciences, Hefei, China
| | - B Tál
- Wigner Research Centre for Physics, Budapest, Hungary
| | - D Dunai
- Wigner Research Centre for Physics, Budapest, Hungary
| | - G Anda
- Wigner Research Centre for Physics, Budapest, Hungary
| | - O Asztalos
- Budapest University of Technology and Economics, Budapest, Hungary
| | - G I Pokol
- Budapest University of Technology and Economics, Budapest, Hungary
| | - S Kálvin
- Wigner Research Centre for Physics, Budapest, Hungary
| | - J Németh
- Wigner Research Centre for Physics, Budapest, Hungary
| | - T Krizsanóczi
- Wigner Research Centre for Physics, Budapest, Hungary
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Réfy DI, Brix M, Gomes R, Tál B, Zoletnik S, Dunai D, Kocsis G, Kálvin S, Szabolics T. Publisher's Note: "Sub-millisecond electron density profile measurement at the JET tokamak with the fast lithium beam emission spectroscopy system" [Rev. Sci. Instrum. 89, 043509 (2018)]. Rev Sci Instrum 2018; 89:069902. [PMID: 29960537 DOI: 10.1063/1.5043551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Affiliation(s)
- D I Réfy
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - M Brix
- CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB, United Kingdom
| | - R Gomes
- Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - B Tál
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - S Zoletnik
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - D Dunai
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - G Kocsis
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - S Kálvin
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - T Szabolics
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
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Réfy DI, Brix M, Gomes R, Tál B, Zoletnik S, Dunai D, Kocsis G, Kálvin S, Szabolics T. Sub-millisecond electron density profile measurement at the JET tokamak with the fast lithium beam emission spectroscopy system. Rev Sci Instrum 2018; 89:043509. [PMID: 29716310 DOI: 10.1063/1.4986621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Diagnostic alkali atom (e.g., lithium) beams are routinely used to diagnose magnetically confined plasmas, namely, to measure the plasma electron density profile in the edge and the scrape off layer region. A light splitting optics system was installed into the observation system of the lithium beam emission spectroscopy diagnostic at the Joint European Torus (JET) tokamak, which allows simultaneous measurement of the beam light emission with a spectrometer and a fast avalanche photodiode (APD) camera. The spectrometer measurement allows density profile reconstruction with ∼10 ms time resolution, absolute position calculation from the Doppler shift, spectral background subtraction as well as relative intensity calibration of the channels for each discharge. The APD system is capable of measuring light intensities on the microsecond time scale. However ∼100 μs integration is needed to have an acceptable signal to noise ratio due to moderate light levels. Fast modulation of the beam up to 30 kHz is implemented which allows background subtraction on the 100 μs time scale. The measurement covers the 0.9 < ρpol < 1.1 range with 6-10 mm optical resolution at the measurement location which translates to 3-5 mm radial resolution at the midplane due to flux expansion. An automated routine has been developed which performs the background subtraction, the relative calibration, and the comprehensive error calculation, runs a Bayesian density reconstruction code, and loads results to the JET database. The paper demonstrates the capability of the APD system by analyzing fast phenomena like pellet injection and edge localized modes.
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Affiliation(s)
- D I Réfy
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - M Brix
- CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB, United Kingdom
| | - R Gomes
- Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - B Tál
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - S Zoletnik
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - D Dunai
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - G Kocsis
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - S Kálvin
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
| | - T Szabolics
- Wigner Research Centre for Physics, XII Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary
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Anda G, Dunai D, Lampert M, Krizsanóczi T, Németh J, Bató S, Nam YU, Hu GH, Zoletnik S. Development of a high current 60 keV neutral lithium beam injector for beam emission spectroscopy measurements on fusion experiments. Rev Sci Instrum 2018; 89:013503. [PMID: 29390651 DOI: 10.1063/1.5004126] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A 60 keV neutral lithium beam system was designed and built up for beam emission spectroscopy measurement of edge plasma on the KSTAR and EAST tokamaks. The electron density profile and its fluctuation can be measured using the accelerated lithium beam-based emission spectroscopy system. A thermionic ion source was developed with a SiC heater to emit around 4-5 mA ion current from a 14 mm diameter surface. The ion optic is following the 2 step design used on other devices with small modifications to reach about 2-3 cm beam diameter in the plasma at about 4 m from the ion source. A newly developed recirculating sodium vapour neutralizer neutralizes the accelerated ion beam at around 260-280 °C even during long (<20 s) discharges. A set of new beam diagnostic and manipulation techniques are applied to allow optimization, aiming, cleaning, and beam modulation. The maximum 60 keV beam energy with 4 mA ion current was successfully reached at KSTAR and at EAST. Combined with an efficient observation system, the Li-beam diagnostic enables the measurement of the density profile and fluctuations on the plasma turbulence time scale.
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Affiliation(s)
- G Anda
- Wigner RCP, EURATOM Association HAS, P.O. Box 49, Budapest H-1525, Hungary
| | - D Dunai
- Wigner RCP, EURATOM Association HAS, P.O. Box 49, Budapest H-1525, Hungary
| | - M Lampert
- Wigner RCP, EURATOM Association HAS, P.O. Box 49, Budapest H-1525, Hungary
| | - T Krizsanóczi
- Wigner RCP, EURATOM Association HAS, P.O. Box 49, Budapest H-1525, Hungary
| | - J Németh
- Wigner RCP, EURATOM Association HAS, P.O. Box 49, Budapest H-1525, Hungary
| | - S Bató
- Wigner RCP, EURATOM Association HAS, P.O. Box 49, Budapest H-1525, Hungary
| | - Y U Nam
- National Fusion Research Institute, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-333, South Korea
| | - G H Hu
- Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, China
| | - S Zoletnik
- Wigner RCP, EURATOM Association HAS, P.O. Box 49, Budapest H-1525, Hungary
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Zoletnik S, Biedermann C, Cseh G, Kocsis G, König R, Szabolics T, Szepesi T. First results of the multi-purpose real-time processing video camera system on the Wendelstein 7-X stellarator and implications for future devices. Rev Sci Instrum 2018; 89:013502. [PMID: 29390718 DOI: 10.1063/1.4995947] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A special video camera has been developed for the 10-camera overview video system of the Wendelstein 7-X (W7-X) stellarator considering multiple application needs and limitations resulting from this complex long-pulse superconducting stellarator experiment. The event detection intelligent camera (EDICAM) uses a special 1.3 Mpixel CMOS sensor with non-destructive read capability which enables fast monitoring of smaller Regions of Interest (ROIs) even during long exposures. The camera can perform simple data evaluation algorithms (minimum/maximum, mean comparison to levels) on the ROI data which can dynamically change the readout process and generate output signals. Multiple EDICAM cameras were operated in the first campaign of W7-X and capabilities were explored in the real environment. Data prove that the camera can be used for taking long exposure (10-100 ms) overview images of the plasma while sub-ms monitoring and even multi-camera correlated edge plasma turbulence measurements of smaller areas can be done in parallel. These latter revealed that filamentary turbulence structures extend between neighboring modules of the stellarator. Considerations emerging for future upgrades of this system and similar setups on future long-pulse fusion experiments such as ITER are discussed.
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Affiliation(s)
- S Zoletnik
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
| | - C Biedermann
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - G Cseh
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
| | - G Kocsis
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
| | - R König
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Szabolics
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
| | - T Szepesi
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
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Krychowiak M, Adnan A, Alonso A, Andreeva T, Baldzuhn J, Barbui T, Beurskens M, Biel W, Biedermann C, Blackwell BD, Bosch HS, Bozhenkov S, Brakel R, Bräuer T, Brotas de Carvalho B, Burhenn R, Buttenschön B, Cappa A, Cseh G, Czarnecka A, Dinklage A, Drews P, Dzikowicka A, Effenberg F, Endler M, Erckmann V, Estrada T, Ford O, Fornal T, Frerichs H, Fuchert G, Geiger J, Grulke O, Harris JH, Hartfuß HJ, Hartmann D, Hathiramani D, Hirsch M, Höfel U, Jabłoński S, Jakubowski MW, Kaczmarczyk J, Klinger T, Klose S, Knauer J, Kocsis G, König R, Kornejew P, Krämer-Flecken A, Krawczyk N, Kremeyer T, Książek I, Kubkowska M, Langenberg A, Laqua HP, Laux M, Lazerson S, Liang Y, Liu SC, Lorenz A, Marchuk AO, Marsen S, Moncada V, Naujoks D, Neilson H, Neubauer O, Neuner U, Niemann H, Oosterbeek JW, Otte M, Pablant N, Pasch E, Sunn Pedersen T, Pisano F, Rahbarnia K, Ryć L, Schmitz O, Schmuck S, Schneider W, Schröder T, Schuhmacher H, Schweer B, Standley B, Stange T, Stephey L, Svensson J, Szabolics T, Szepesi T, Thomsen H, Travere JM, Trimino Mora H, Tsuchiya H, Weir GM, Wenzel U, Werner A, Wiegel B, Windisch T, Wolf R, Wurden GA, Zhang D, Zimbal A, Zoletnik S. Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited). Rev Sci Instrum 2016; 87:11D304. [PMID: 27910389 DOI: 10.1063/1.4964376] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. An overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.
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Affiliation(s)
- M Krychowiak
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A Adnan
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A Alonso
- Laboratorio Nacional de Fusión, CIEMAT, Avenida Complutense, Madrid, Spain
| | - T Andreeva
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - J Baldzuhn
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Barbui
- University of Wisconsin, Engineering Drive, Madison, Wisconsin 53706, USA
| | - M Beurskens
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - W Biel
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - C Biedermann
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - B D Blackwell
- Australian National University, Acton ACT, 2601 Canberra, Australia
| | - H S Bosch
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - S Bozhenkov
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - R Brakel
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Bräuer
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - B Brotas de Carvalho
- Instituto de Plasmas e Fusao Nuclear, Avenue Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - R Burhenn
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - B Buttenschön
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A Cappa
- Laboratorio Nacional de Fusión, CIEMAT, Avenida Complutense, Madrid, Spain
| | - G Cseh
- Wigner Research Centre for Physics, Konkoly Thege 29-33, H-1121 Budapest, Hungary
| | - A Czarnecka
- Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw, Poland
| | - A Dinklage
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - P Drews
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - A Dzikowicka
- University of Szczecin, al. Papieża Jana Pawła II 22A, Szczecin, Poland
| | - F Effenberg
- University of Wisconsin, Engineering Drive, Madison, Wisconsin 53706, USA
| | - M Endler
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - V Erckmann
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Estrada
- Laboratorio Nacional de Fusión, CIEMAT, Avenida Complutense, Madrid, Spain
| | - O Ford
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Fornal
- Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw, Poland
| | - H Frerichs
- University of Wisconsin, Engineering Drive, Madison, Wisconsin 53706, USA
| | - G Fuchert
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - J Geiger
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - O Grulke
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - J H Harris
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H J Hartfuß
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - D Hartmann
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - D Hathiramani
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - M Hirsch
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - U Höfel
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - S Jabłoński
- Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw, Poland
| | - M W Jakubowski
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - J Kaczmarczyk
- Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw, Poland
| | - T Klinger
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - S Klose
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - J Knauer
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - G Kocsis
- Wigner Research Centre for Physics, Konkoly Thege 29-33, H-1121 Budapest, Hungary
| | - R König
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - P Kornejew
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A Krämer-Flecken
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - N Krawczyk
- Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw, Poland
| | - T Kremeyer
- University of Wisconsin, Engineering Drive, Madison, Wisconsin 53706, USA
| | - I Książek
- Opole University, pl. Kopernika 11a, 45-040 Opole, Poland
| | - M Kubkowska
- Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw, Poland
| | - A Langenberg
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - H P Laqua
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - M Laux
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - S Lazerson
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - Y Liang
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - S C Liu
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - A Lorenz
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A O Marchuk
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - S Marsen
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - V Moncada
- CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
| | - D Naujoks
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - H Neilson
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - O Neubauer
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - U Neuner
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - H Niemann
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - J W Oosterbeek
- Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - M Otte
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - N Pablant
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - E Pasch
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Sunn Pedersen
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - F Pisano
- University of Cagliari, Via Università, 40, 09124 Cagliari, Italy
| | - K Rahbarnia
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - L Ryć
- Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw, Poland
| | - O Schmitz
- University of Wisconsin, Engineering Drive, Madison, Wisconsin 53706, USA
| | - S Schmuck
- Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - W Schneider
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Schröder
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - H Schuhmacher
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - B Schweer
- Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
| | - B Standley
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Stange
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - L Stephey
- University of Wisconsin, Engineering Drive, Madison, Wisconsin 53706, USA
| | - J Svensson
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Szabolics
- Wigner Research Centre for Physics, Konkoly Thege 29-33, H-1121 Budapest, Hungary
| | - T Szepesi
- Wigner Research Centre for Physics, Konkoly Thege 29-33, H-1121 Budapest, Hungary
| | - H Thomsen
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - J-M Travere
- CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
| | - H Trimino Mora
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - H Tsuchiya
- NIFS National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
| | - G M Weir
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - U Wenzel
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A Werner
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - B Wiegel
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - T Windisch
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - R Wolf
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - G A Wurden
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D Zhang
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A Zimbal
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - S Zoletnik
- Wigner Research Centre for Physics, Konkoly Thege 29-33, H-1121 Budapest, Hungary
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Son S, Hong S, Kim J, Kim JY, Kim H, Ding F, Luo G, Németh J, Zoletnik S, Fenyvesi A, Pitts R. Multi-purpose mid-plane manipulator for plasma surface interaction research in KSTAR. Fusion Engineering and Design 2016. [DOI: 10.1016/j.fusengdes.2016.03.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ayllon-Guerola J, Gonzalez-Martin J, Garcia-Munoz M, Rivero-Rodriguez J, Herrmann A, Vorbrugg S, Leitenstern P, Zoletnik S, Galdon J, Garcia Lopez J, Rodriguez-Ramos M, Sanchis-Sanchez L, Dominguez AD, Kocan M, Gunn JP, Garcia-Vallejo D, Dominguez J. A fast feedback controlled magnetic drive for the ASDEX Upgrade fast-ion loss detectors. Rev Sci Instrum 2016; 87:11E705. [PMID: 27910655 DOI: 10.1063/1.4959913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A magnetically driven fast-ion loss detector system for the ASDEX Upgrade tokamak has been designed and will be presented here. The device is feedback controlled to adapt the detector head position to the heat load and physics requirements. Dynamic simulations have been performed taking into account effects such as friction, coil self-induction, and eddy currents. A real time positioning control algorithm to maximize the detector operational window has been developed. This algorithm considers dynamical behavior and mechanical resistance as well as measured and predicted thermal loads. The mechanical design and real time predictive algorithm presented here may be used for other reciprocating systems.
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Affiliation(s)
- J Ayllon-Guerola
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - J Gonzalez-Martin
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - M Garcia-Munoz
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - J Rivero-Rodriguez
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - A Herrmann
- Max-Planck-Institut für Plasmaphysik, Garching, Germany
| | - S Vorbrugg
- Max-Planck-Institut für Plasmaphysik, Garching, Germany
| | - P Leitenstern
- Max-Planck-Institut für Plasmaphysik, Garching, Germany
| | | | - J Galdon
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - J Garcia Lopez
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - M Rodriguez-Ramos
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - L Sanchis-Sanchez
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - A D Dominguez
- Department of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, Spain
| | - M Kocan
- ITER Organization, Route de Vinon sur Verdon, 13115 St Paul Lez Durance, France
| | - J P Gunn
- CEA, IRFM, F-13108 Saint Paul Lez Durance, France
| | | | - J Dominguez
- ETSI, University of Seville, 41092 Seville, Spain
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Anda G, Bencze A, Berta M, Dunai D, Hacek P, Krbec J, Réfy D, Krizsanóczi T, Bató S, Ilkei T, Kiss I, Veres G, Zoletnik S. Lithium beam diagnostic system on the COMPASS tokamak. Fusion Engineering and Design 2016. [DOI: 10.1016/j.fusengdes.2016.04.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Kocsis G, Baross T, Biedermann C, Bodnár G, Cseh G, Ilkei T, König R, Otte M, Szabolics T, Szepesi T, Zoletnik S. Overview video diagnostics for the W7-X stellarator. Fusion Engineering and Design 2015. [DOI: 10.1016/j.fusengdes.2015.02.067] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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23
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Lampert M, Anda G, Czopf A, Erdei G, Guszejnov D, Kovácsik Á, Pokol GI, Réfy D, Nam YU, Zoletnik S. Combined hydrogen and lithium beam emission spectroscopy observation system for Korea Superconducting Tokamak Advanced Research. Rev Sci Instrum 2015; 86:073501. [PMID: 26233377 DOI: 10.1063/1.4923251] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A novel beam emission spectroscopy observation system was designed, built, and installed onto the Korea Superconducting Tokamak Advanced Research tokamak. The system is designed in a way to be capable of measuring beam emission either from a heating deuterium or from a diagnostic lithium beam. The two beams have somewhat complementary capabilities: edge density profile and turbulence measurement with the lithium beam and two dimensional turbulence measurement with the heating beam. Two detectors can be used in parallel: a CMOS camera provides overview of the scene and lithium beam light intensity distribution at maximum few hundred Hz frame rate, while a 4 × 16 pixel avalanche photo-diode (APD) camera gives 500 kHz bandwidth data from a 4 cm × 16 cm region. The optics use direct imaging through lenses and mirrors from the observation window to the detectors, thus avoid the use of costly and inflexible fiber guides. Remotely controlled mechanisms allow adjustment of the APD camera's measurement location on a shot-to-shot basis, while temperature stabilized filter holders provide selection of either the Doppler shifted deuterium alpha or lithium resonance line. The capabilities of the system are illustrated by measurements of basic plasma turbulence properties.
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Affiliation(s)
- M Lampert
- Wigner RCP, Euratom Association-HAS, Budapest, Hungary
| | - G Anda
- Wigner RCP, Euratom Association-HAS, Budapest, Hungary
| | - A Czopf
- Department of Atomic Physics, BME IOP, Budapest, Hungary
| | - G Erdei
- Department of Atomic Physics, BME IOP, Budapest, Hungary
| | | | | | | | - D Réfy
- Wigner RCP, Euratom Association-HAS, Budapest, Hungary
| | - Y U Nam
- National Fusion Research Institute, Daejeon, Korea
| | - S Zoletnik
- Wigner RCP, Euratom Association-HAS, Budapest, Hungary
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Nam YU, Zoletnik S, Lampert M, Kovácsik Á, Wi HM. Edge electron density profiles and fluctuations measured by two-dimensional beam emission spectroscopy in the KSTAR. Rev Sci Instrum 2014; 85:11E434. [PMID: 25430341 DOI: 10.1063/1.4894839] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Beam emission spectroscopy (BES) system in Korea Superconducting Tokamak Advanced Research (KSTAR) has recently been upgraded. The background intensity was reduced from 30% to 2% by suppressing the stray lights. This allows acquisition of the relative electron density profiles on the plasma edge without background subtraction from the beam power modulation signals. The KSTAR BES system has its spatial resolution of 1 cm, the temporal resolution of 2 MHz, and a total 32 channel (8 radial × 4 poloidal) avalanche photo diode array. Most measurements were done on the plasma edge, r/a ∼ 0.9, with 8 cm radial measurement width that covers the pedestal range. High speed density profile measurements reveal temporal behaviors of fast transient events, such as the precursors of edge localized modes and the transitions between confinement modes. Low background level also allows analysis of the edge density fluctuation patterns with reduced background fluctuations. Propagation of the density structures can be investigated by comparing the phase delays between the spatially distributed channels.
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Affiliation(s)
- Y U Nam
- National Fusion Research Institute, Daejeon, South Korea
| | - S Zoletnik
- Wigner RCP Institute for Particle and Nuclear Physics, Budapest, Hungary
| | - M Lampert
- Wigner RCP Institute for Particle and Nuclear Physics, Budapest, Hungary
| | - Ákos Kovácsik
- Institute of Nuclear Techniques, Budapest Technical University, Budapest, Hungary
| | - H M Wi
- National Fusion Research Institute, Daejeon, South Korea
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König R, Biel W, Biedermann C, Burhenn R, Cseh G, Czarnecka A, Endler M, Estrada T, Grulke O, Hathiramani D, Hirsch M, Jabłonski S, Jakubowski M, Kaczmarczyk J, Kasparek W, Kocsis G, Kornejew P, Krämer-Flecken A, Krychowiak M, Kubkowska M, Langenberg A, Laux M, Liang Y, Lorenz A, Neubauer O, Otte M, Pablant N, Pasch E, Pedersen TS, Schmitz O, Schneider W, Schuhmacher H, Schweer B, Thomsen H, Szepesi T, Wiegel B, Windisch T, Wolf S, Zhang D, Zoletnik S. Status of the diagnostics development for the first operation phase of the stellarator Wendelstein 7-X. Rev Sci Instrum 2014; 85:11D818. [PMID: 25430231 DOI: 10.1063/1.4889905] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An overview of the diagnostics which are essential for the first operational phase of Wendelstein 7-X and the set of diagnostics expected to be ready for operation at this time are presented. The ongoing investigations of how to cope with high levels of stray Electron Cyclotron Resonance Heating (ECRH) radiation in the ultraviolet (UV)/visible/infrared (IR) optical diagnostics are described.
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Affiliation(s)
- R König
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - W Biel
- Institute of Energy and Climate Research, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - C Biedermann
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - R Burhenn
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - G Cseh
- Wigner RCP, RMI, Konkoly Thege 219-33, H-1121 Budapest, Hungary
| | - A Czarnecka
- IFPiLM, Hery Street 23, 01-497 Warsaw, Poland
| | - M Endler
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Estrada
- Laboratorio Nacional de Fusion, CIEMAT, Avenida Complutense, Madrid, Spain
| | - O Grulke
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - D Hathiramani
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - M Hirsch
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - S Jabłonski
- IFPiLM, Hery Street 23, 01-497 Warsaw, Poland
| | - M Jakubowski
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | | | - W Kasparek
- IGVP, Universität Stuttgart, Pfaffenwaldring 31, 70569 Stuttgart, Germany
| | - G Kocsis
- Wigner RCP, RMI, Konkoly Thege 219-33, H-1121 Budapest, Hungary
| | - P Kornejew
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - A Krämer-Flecken
- Institute of Energy and Climate Research, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - M Krychowiak
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - M Kubkowska
- IFPiLM, Hery Street 23, 01-497 Warsaw, Poland
| | - A Langenberg
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - M Laux
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - Y Liang
- Institute of Energy and Climate Research, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - A Lorenz
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - O Neubauer
- Institute of Energy and Climate Research, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - M Otte
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - N Pablant
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - E Pasch
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T S Pedersen
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - O Schmitz
- Department of Engineering Physics, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, Wisconsin 53706, USA
| | - W Schneider
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - H Schuhmacher
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - B Schweer
- Institute of Energy and Climate Research, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - H Thomsen
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - T Szepesi
- Wigner RCP, RMI, Konkoly Thege 219-33, H-1121 Budapest, Hungary
| | - B Wiegel
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - T Windisch
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - S Wolf
- IGVP, Universität Stuttgart, Pfaffenwaldring 31, 70569 Stuttgart, Germany
| | - D Zhang
- Max Planck Institute for Plasma Physics, 17491 Greifswald, Germany
| | - S Zoletnik
- Wigner RCP, RMI, Konkoly Thege 219-33, H-1121 Budapest, Hungary
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26
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Berta M, Anda G, Aradi M, Bencze A, Buday C, Kiss I, Tulipán S, Veres G, Zoletnik S, Havlícek J, Háček P. Development of atomic beam probe for tokamaks. Fusion Engineering and Design 2013. [DOI: 10.1016/j.fusengdes.2013.05.064] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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27
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Pokol G, Zoletnik S, Dunai D, Marchuk O, Baross T, Erdei G, Grunda G, Kiss I, Kovacsik A, v.Hellermann M, Lischtschenko O, Biel W, Jaspers R, Durkut M. Fluctuation BES measurements with the ITER core CXRS prototype spectrometer. Fusion Engineering and Design 2013. [DOI: 10.1016/j.fusengdes.2013.02.171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Xu Y, Hidalgo C, Shesterikov I, Krämer-Flecken A, Zoletnik S, Van Schoor M, Vergote M. Isotope effect and multiscale physics in fusion plasmas. Phys Rev Lett 2013; 110:265005. [PMID: 24015403 DOI: 10.1103/physrevlett.110.265005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The mechanism governing the impact of the mass isotope on plasma confinement is still one of the main scientific conundrums facing the magnetic fusion community after more than thirty years of intense research. We have investigated the properties of local turbulence and long-range correlations in hydrogen and deuterium plasmas in the TEXTOR tokamak. Experimental findings have shown a systematic increasing in the amplitude of long-range correlations during the transition from hydrogen to deuterium dominated plasmas. These results provide the first direct experimental evidence of the importance of multiscale physics for unraveling the physics of the isotope effect in fusion plasmas.
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Affiliation(s)
- Y Xu
- Laboratoire de Physique des Plasmas-Laboratorium voor Plasmafysica, Ecole Royale Militaire-Koninklijke Militaire School, Trilateral Euregio Cluster, B-1000 Brussels, Belgium.
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30
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Ghim YC, Schekochihin AA, Field AR, Abel IG, Barnes M, Colyer G, Cowley SC, Parra FI, Dunai D, Zoletnik S. Experimental signatures of critically balanced turbulence in MAST. Phys Rev Lett 2013; 110:145002. [PMID: 25166998 DOI: 10.1103/physrevlett.110.145002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Indexed: 06/03/2023]
Abstract
Beam emission spectroscopy (BES) measurements of ion-scale density fluctuations in the MAST tokamak are used to show that the turbulence correlation time, the drift time associated with ion temperature or density gradients, the particle (ion) streaming time along the magnetic field, and the magnetic drift time are consistently comparable, suggesting a "critically balanced" turbulence determined by the local equilibrium. The resulting scalings of the poloidal and radial correlation lengths are derived and tested. The nonlinear time inferred from the density fluctuations is longer than the other times; its ratio to the correlation time scales as ν(*i)(-0.8 ± 0.1), where ν(*i) = ion collision rate/streaming rate. This is consistent with turbulent decorrelation being controlled by a zonal component, invisible to the BES, with an amplitude exceeding those of the drift waves by ∼ ν(*i)(-0.8).
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Affiliation(s)
- Y-C Ghim
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, United Kingdom and EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, United Kingdom and Department of Nuclear and Quantum Engineering, KAIST, Daejeon 305-701, Republic of Korea
| | - A A Schekochihin
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, United Kingdom and Merton College, Oxford OX1 4JD, United Kingdom
| | - A R Field
- EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - I G Abel
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, United Kingdom and Merton College, Oxford OX1 4JD, United Kingdom
| | - M Barnes
- Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA and Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37831, USA
| | - G Colyer
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, United Kingdom and EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - S C Cowley
- EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, United Kingdom and Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom
| | - F I Parra
- Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA
| | - D Dunai
- Wigner Research Centre for Physics, Association EURATOM/HAS, P.O. Box 49, H-1525 Budapest, Hungary
| | - S Zoletnik
- Wigner Research Centre for Physics, Association EURATOM/HAS, P.O. Box 49, H-1525 Budapest, Hungary
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31
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König R, Baldzuhn J, Biedermann C, Burhenn R, Bozhenkov S, Cardella A, Endler M, Hartfuss HJ, Hathiramani D, Hildebrandt D, Hirsch M, Jakubowski M, Kocsis G, Kornejev P, Krychowiak M, Laqua HP, Laux M, Oosterbeek JW, Pasch E, Richert T, Schneider W, Sunn-Pedersen T, Thomsen H, Weller A, Werner A, Wolf R, Zhang D, Zoletnik S. Diagnostics development for quasi-steady-state operation of the Wendelstein 7-X stellarator (invited). Rev Sci Instrum 2012; 83:10D730. [PMID: 23126902 DOI: 10.1063/1.4733531] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The critical issues in the development of diagnostics, which need to work robust and reliable under quasi-steady state conditions for the discharge durations of 30 min and which cannot be maintained throughout the one week duration of each operation phase of the Wendelstein 7-X stellarator, are being discussed.
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Affiliation(s)
- R König
- Max-Planck-Institut für Plasmaphysik, EURATOM Association, Greifswald, Germany.
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32
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Brix M, Dodt D, Dunai D, Lupelli I, Marsen S, Melson TF, Meszaros B, Morgan P, Petravich G, Refy DI, Silva C, Stamp M, Szabolics T, Zastrow KD, Zoletnik S. Recent improvements of the JET lithium beam diagnostic. Rev Sci Instrum 2012; 83:10D533. [PMID: 23130794 DOI: 10.1063/1.4739411] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A 60 kV neutral lithium diagnostic beam probes the edge plasma of JET for the measurement of electron density profiles. This paper describes recent enhancements of the diagnostic setup, new procedures for calibration and protection measures for the lithium ion gun during massive gas puffs for disruption mitigation. New light splitting optics allow in parallel beam emission measurements with a new double entrance slit CCD spectrometer (spectrally resolved) and a new interference filter avalanche photodiode camera (fast density and fluctuation studies).
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Affiliation(s)
- M Brix
- EURATOM∕CCFE Fusion Association, Culham Science Centre, OX14 3DB Abingdon, United Kingdom.
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33
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Jaspers RJE, Scheffer M, Kappatou A, van der Valk NCJ, Durkut M, Snijders B, Marchuk O, Biel W, Pokol GI, Erdei G, Zoletnik S, Dunai D. A high etendue spectrometer suitable for core charge eXchange recombination spectroscopy on ITER. Rev Sci Instrum 2012; 83:10D515. [PMID: 23126857 DOI: 10.1063/1.4732058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A feasibility study for the use of core charge exchange recombination spectroscopy on ITER has shown that accurate measurements on the helium ash require a spectrometer with a high etendue of 1mm(2)sr to comply with the measurement requirements [S. Tugarinov et al., Rev. Sci. Instrum. 74, 2075 (2003)]. To this purpose such an instrument has been developed consisting of three separate wavelength channels (to measure simultaneously He/Be, C/Ne, and H/D/T together with the Doppler shifted direct emission of the diagnostic neutral beam, the beam emission (BES) signal), combining high dispersion (0.02 nm/pixel), sufficient resolution (0.2 nm), high efficiency (55%), and extended wavelength range (14 nm) at high etendue. The combined measurement of the BES along the same sightline within a third wavelength range provides the possibility for in situ calibration of the charge eXchange recombination spectroscopy signals. In addition, the option is included to use the same instrument for measurements of the fast fluctuations of the beam emission intensity up to 2 MHz, with the aim to study MHD activity.
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Affiliation(s)
- R J E Jaspers
- Science and Technology of Nuclear Fusion, Eindhoven University of Technology, Eindhoven, The Netherlands.
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Nam YU, Zoletnik S, Lampert M, Kovácsik Á. Analysis of edge density fluctuation measured by trial KSTAR beam emission spectroscopy system. Rev Sci Instrum 2012; 83:10D531. [PMID: 23126870 DOI: 10.1063/1.4739078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A beam emission spectroscopy (BES) system based on direct imaging avalanche photodiode (APD) camera has been designed for Korea Superconducting Tokamak Advanced Research (KSTAR) and a trial system has been constructed and installed for evaluating feasibility of the design. The system contains two cameras, one is an APD camera for BES measurement and another is a fast visible camera for position calibration. Two pneumatically actuated mirrors were positioned at front and rear of lens optics. The front mirror can switch the measurement between edge and core region of plasma and the rear mirror can switch between the APD and the visible camera. All systems worked properly and the measured photon flux was reasonable as expected from the simulation. While the measurement data from the trial system were limited, it revealed some interesting characteristics of KSTAR plasma suggesting future research works with fully installed BES system. The analysis result and the development plan will be presented in this paper.
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Affiliation(s)
- Y U Nam
- National Fusion Research Institute, Daejeon, South Korea.
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35
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Field AR, Dunai D, Gaffka R, Ghim YC, Kiss I, Mészáros B, Krizsanóczi T, Shibaev S, Zoletnik S. Beam emission spectroscopy turbulence imaging system for the MAST spherical tokamak. Rev Sci Instrum 2012; 83:013508. [PMID: 22299952 DOI: 10.1063/1.3669756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A new beam emission spectroscopy turbulence imaging system has recently been installed onto the MAST spherical tokamak. The system utilises a high-throughput, direct coupled imaging optics, and a single large interference filter for collection of the Doppler shifted D(α) emission from the ~2 MW heating beam of ~70 keV injection energy. The collected light is imaged onto a 2D array detector with 8 × 4 avalanche photodiode sensors which is incorporated into a custom camera unit to perform simultaneous 14-bit digitization at 2 MHz of all 32 channels. The array is imaged at the beam to achieve a spatial resolution of ~2 cm in the radial (horizontal) and poloidal (vertical) directions, which is sufficient for detection of the ion-scale plasma turbulence. At the typical photon fluxes of ~10(11) s(-1) the achieved signal-to-noise ratio of ~300 at the 0.5 MHz analogue bandwidth is sufficient for detection of relative density fluctuations at the level of a few 0.1%. The system is to be utilised for the study of the characteristics of the broadband, ion-scale turbulence, in particular its interaction with flow shear, as well as coherent fluctuations due to various types of MHD activity.
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Affiliation(s)
- A R Field
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon, United Kingdom
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Abstract
An avalanche photodiode based (APD) detector for the visible wavelength range was developed for low light level, high frequency beam emission spectroscopy (BES) experiments in fusion plasmas. This solid state detector has higher quantum efficiency than photomultiplier tubes, and unlike normal photodiodes, it has internal gain. This paper describes the developed detector as well as the noise model of the electronic circuit. By understanding the noise sources and the amplification process, the optimal amplifier and APD reverse voltage setting can be determined, where the signal-to-noise ratio is the highest for a given photon flux. The calculations are compared to the absolute calibration results of the implemented circuit. It was found that for a certain photon flux range, relevant for BES measurements (≈10(8)-10(10) photons/s), the new detector is superior to both photomultipliers and photodiodes, although it does not require cryogenic cooling of any component. The position of this photon flux window sensitively depends on the parameters of the actual experimental implementation (desired bandwidth, detector size, etc.) Several detector units based on these developments have been built and installed in various tokamaks. Some illustrative results are presented from the 8-channel trial BES system installed at Mega-Ampere Spherical Tokamak (MAST) and the 16-channel BES system installed at the Torus Experiment for Technology Oriented Research (TEXTOR).
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Affiliation(s)
- D Dunai
- KFKI Research Institute for Particle and Nuclear Physics, EURATOM Association, P.O. Box 49, H-1525 Budapest, Hungary
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37
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Brix M, Dodt D, Korotkov A, Morgan P, Dunai D, Fischer R, Meigs A, Nedzelskiy IS, Schweinzer J, Vince J, Zoletnik S. Upgrade of the lithium beam diagnostic at JET. Rev Sci Instrum 2010; 81:10D733. [PMID: 21061477 DOI: 10.1063/1.3502320] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A 60 kV neutral Li beam is injected into the edge plasma of JET to measure the electron density. The beam observation system has been improved by replacing a Czerny-Turner spectrometer with a high-resolution transmission-grating spectrometer and a fast back-illuminated frame-transfer camera. The larger throughput of the spectrometer, the increased sensitivity, and the faster readout of the new camera allow inter-ELM (edge localized mode) measurements (frame rate of 100 Hz). The calibration of the setup, as well as an improved spectral fitting technique in the presence of carbon background radiation, is discussed in detail. The density calculation is based on a statistical analysis method. Results are presented for different plasma scenarios.
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Affiliation(s)
- M Brix
- EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, United Kingdom.
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38
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Ghim Kim YC, Field AR, Zoletnik S, Dunai D. Calculation of spatial response of 2D beam emission spectroscopy diagnostic on MAST. Rev Sci Instrum 2010; 81:10D713. [PMID: 21033906 DOI: 10.1063/1.3479037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The beam emission spectroscopy (BES) turbulence diagnostic on MAST is to be upgraded in June 2010 from a one-dimensional trial system to a two-dimensional imaging system (8 radial×4 poloidal channels) based on a newly developed avalanche photodiode array camera. The spatial resolution of the new system is calculated in terms of the point spread function to account for the effects of field-line curvature, observation geometry, the finite lifetime of the excited state of the beam atoms, and beam attenuation and divergence. It is found that the radial spatial resolution is ∼2-3 cm and the poloidal spatial resolution ∼1-5 cm depending on the radial viewing location. The absolute number of detected photons is also calculated, hence the photon noise level can be determined.
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Affiliation(s)
- Young-Chul Ghim Kim
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3NP, United Kingdom
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König R, Baldzuhn J, Biel W, Biedermann C, Burhenn R, Bozhenkov S, Cantarini J, Dreier H, Endler M, Hartfuss HJ, Hildebrandt D, Hirsch M, Jakubowski M, Jimenez-Gomez R, Kocsis G, Kornejev P, Krychowiak M, Laqua HP, Laux M, Oosterbeek JW, Pasch E, Richert T, Schneider W, Schweer B, Svensson J, Thomsen H, Weller A, Werner A, Wolf R, Zhang D, Zoletnik S. Diagnostics design for steady-state operation of the Wendelstein 7-X stellarator. Rev Sci Instrum 2010; 81:10E133. [PMID: 21033995 DOI: 10.1063/1.3483210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The status of the diagnostic developments for the quasistationary operable stellarator Wendelstein 7-X (maximum pulse length of 30 min at 10 MW ECRH heating at 140 GHz) will be reported on. Significant emphasis is being given to the issue of ECRH stray radiation shielding of in-vessel diagnostic components, which will be critical at high density operation requiring O2 and OXB heating.
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Affiliation(s)
- R König
- Max-Planck-Institute für Plasmaphysik, EURATOM Association, Greifswald D-1749, Germany.
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Szappanos A, Berta M, Hron M, Pánek R, Stöckel J, Tulipán S, Veres G, Weinzettl V, Zoletnik S. EDICAM fast video diagnostic installation on the COMPASS tokamak. Fusion Engineering and Design 2010. [DOI: 10.1016/j.fusengdes.2009.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Pusztai I, Pokol G, Dunai D, Réfy D, Pór G, Anda G, Zoletnik S, Schweinzer J. Deconvolution-based correction of alkali beam emission spectroscopy density profile measurements. Rev Sci Instrum 2009; 80:083502. [PMID: 19725650 DOI: 10.1063/1.3205930] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A deconvolution-based correction method of the beam emission spectroscopy (BES) density profile measurement is demonstrated by its application to simulated measurements of the COMPASS and TEXTOR tokamaks. If the line of sight is far from tangential to the flux surfaces, and the beam width is comparable to the scale length on which the light profile varies, the observation may cause an undesired smoothing of the light profile, resulting in a non-negligible underestimation of the calculated density profile. This effect can be reduced significantly by the emission reconstruction method, which gives an estimate of the emissivity along the beam axis from the measured light profile, taking the finite beam width and the properties of the measurement into account in terms of the transfer function of the observation. Characteristics and magnitude of the mentioned systematic error and its reduction by the introduced method are studied by means of the comprehensive alkali BES simulation code RENATE.
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Affiliation(s)
- I Pusztai
- Department of Radio and Space Science, Chalmers University of Technology, EURATOM-VR Association, SE-41296 Göteborg, Sweden
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Field AR, Dunai D, Conway NJ, Zoletnik S, Sárközi J. Beam emission spectroscopy for density turbulence measurements on the MAST spherical tokamak. Rev Sci Instrum 2009; 80:073503. [PMID: 19655949 DOI: 10.1063/1.3170034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Beam emission spectroscopy (BES) of the energetic deuterium (D(0)) heating beams can provide a means of characterizing the density turbulence in tokamak plasmas. First such measurements have been performed on the MAST spherical tokamak using a trial BES system, which shares the collection optics of the charge-exchange recombination spectroscopy system. This system, with eight spatial channels covering the outer part of the plasma cross section, uses avalanche photodiode detectors with custom preamplifiers to provide measurements at 1 MHz bandwidth with a spatial resolution of 4 cm. Simulations of the measurement, including the beam absorption and excitation, line-of-sight integration of the emission spectrum, and the characteristics of the detection system have been benchmarked against the measured absolute intensity of the Doppler shifted Dalpha fluorescence from the 50 keV beam. This gives confidence in predictions of the performance of a two-dimensional imaging BES system planned for MAST. Correlation techniques have also provided information on the characteristics of the density turbulence at the periphery of L-mode plasmas as well as density perturbations due to coherent magnetohydrodynamic activity at the edge of H-mode plasmas. Precursor oscillations of the density in the pedestal region to edge-localized modes occurring during H-mode plasmas with a single-null diverted magnetic configuration are also observable in the raw signals from the trial BES system.
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Affiliation(s)
- A R Field
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB, United Kingdom
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König R, Cantarini J, Dreier H, Erckmann V, Hildebrandt D, Hirsch M, Kocsis G, Kornejew P, Laux M, Laqua H, Pasch E, Recsei S, Szabó V, Thomsen H, Weller A, Werner A, Wolf R, Ye MY, Zoletnik S. Diagnostic developments for quasicontinuous operation of the Wendelstein 7-X stellarator. Rev Sci Instrum 2008; 79:10F337. [PMID: 19044644 DOI: 10.1063/1.2964998] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The stellarator Wendelstein 7-X will allow for quasicontinuous operation with the duration only being limited to two 30 min discharges per day, at a continuous heating power of 10 MW electron cyclotron resonance heating (ECRH) at 140 GHz, by the capacity of the cooling water reservoir. This will result in high thermal loads on all plasma facing components of 50-100 kW/m(2) from radiation alone and of up to about 500 kW/m(2) on components additionally exposed to convective loads. In high density scenarios toroidally varying ECRH stray radiation levels of 50-200 kW/m(2) need to be coped with, requiring careful material selection and different shielding and hardening techniques. Furthermore, a gradual buildup of coatings on plasma facing optical components, which without any measures being taken, would lead to high transmission losses already within a few days of long pulse operation (equivalent to about 1 year of operation in pulsed devices like JET or ASDEX-upgrade) and therefore needs to be prevented as much as possible. In addition in situ cleaning as well as absolute calibration techniques need to be developed for all plasma facing optical systems. Here we report about some of our efforts to find, for various types of diagnostics, ways to cope with these adverse effects. Moreover, we give a few examples for individual diagnostic specific issues with respect to quasicontinuous operation, such as the development of a special integrator for the magnetic diagnostics as well as special interferometer types which can cope with unavoidable vibrations and slow path length changes due to, e.g., thermal expansion of the plasma vessel.
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Affiliation(s)
- R König
- Euratom Association, Max-Planck-Institut fur Plasmaphysik, Wendelsteinstr. 1, 17491 Greifswald, Germany
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