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Rehman U. Electromagnetic Viscous-Resistive-Drift-Wave Instability in Burning Plasma. JOURNAL OF FUSION ENERGY 2019. [DOI: 10.1007/s10894-019-00219-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2
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Chellaï O, Alberti S, Baquero-Ruiz M, Furno I, Goodman T, Manke F, Plyushchev G, Guidi L, Koehn A, Maj O, Poli E, Hizanidis K, Figini L, Ricci D. Millimeter-Wave Beam Scattering by Field-Aligned Blobs in Simple Magnetized Toroidal Plasmas. PHYSICAL REVIEW LETTERS 2018; 120:105001. [PMID: 29570337 DOI: 10.1103/physrevlett.120.105001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Indexed: 06/08/2023]
Abstract
The first direct experimental measurements of the scattering of a millimeter-wave beam by plasma blobs in a simple magnetized torus are reported. The wavelength of the beam is comparable to the characteristic size of the blob. In situ Langmuir probe measurements show that fluctuations of the electron density induce correlated fluctuations of the transmitted power. A first-principles full-wave model, using conditionally sampled 2D electron density profiles, predicts fluctuations of the millimeter-wave power that are in agreement with experiments.
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Affiliation(s)
- O Chellaï
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - S Alberti
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - M Baquero-Ruiz
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - I Furno
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - T Goodman
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - F Manke
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - G Plyushchev
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - L Guidi
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - A Koehn
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
- Institute of Interfacial Process Engineering and Plasma Technology, University of Stuttgart, 70174 Stuttgart, Germany
| | - O Maj
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - E Poli
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - K Hizanidis
- National Technical University of Athens, 106 82 Athens, Greece
| | - L Figini
- Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, 20125 Milan, Italy
| | - D Ricci
- Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, 20125 Milan, Italy
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Spolaore M, Kovařík K, Stöckel J, Adamek J, Dejarnac R, Ďuran I, Komm M, Markovic T, Martines E, Panek R, Seidl J, Vianello N. Electromagnetic ELM and inter-ELM filaments detected in the COMPASS Scrape-Off Layer. NUCLEAR MATERIALS AND ENERGY 2017. [DOI: 10.1016/j.nme.2016.12.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Baquero-Ruiz M, Avino F, Chellai O, Fasoli A, Furno I, Jacquier R, Manke F, Patrick S. Dual Langmuir-probe array for 3D plasma studies in TORPEX. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:113504. [PMID: 27910384 DOI: 10.1063/1.4968024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 11/06/2016] [Indexed: 06/06/2023]
Abstract
We have designed and installed a new Langmuir-probe (LP) array diagnostic to determine basic three-dimensional (3D) features of plasmas in TORPEX. The diagnostic consists of two identical LP arrays, placed on opposite sides of the apparatus, which provide comprehensive coverage of the poloidal cross section at the two different toroidal locations. Cross correlation studies of signals from the arrays provide a basic way to extract 3D information from the plasmas, as experiments show. Moreover, the remarkable signal-to-noise performance of the front-end electronics allows us to follow a different approach in which we combine information from all probes in both arrays to reconstruct elementary 3D plasma structures at each acquisition time step. Then, through data analysis, we track the structures as they evolve in time. The LP arrays include a linear-motion mechanism that can displace radially the probes located on the low field side for experiments that require fine-tuning of the probe locations, and for operational compatibility with the recently installed in-vessel toroidal conductor.
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Affiliation(s)
- M Baquero-Ruiz
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - F Avino
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - O Chellai
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - A Fasoli
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - I Furno
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - R Jacquier
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - F Manke
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - S Patrick
- Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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Bovet A, Fasoli A, Ricci P, Furno I, Gustafson K. Nondiffusive transport regimes for suprathermal ions in turbulent plasmas. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:041101. [PMID: 25974432 DOI: 10.1103/physreve.91.041101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Indexed: 06/04/2023]
Abstract
The understanding of the transport of suprathermal ions in the presence of turbulence is important for fusion plasmas in the burning regime that will characterize reactors, and for space plasmas to understand the physics of particle acceleration. Here, three-dimensional measurements of a suprathermal ion beam in the toroidal plasma device TORPEX are presented. These measurements demonstrate, in a turbulent plasma, the existence of subdiffusive and superdiffusive transport of suprathermal ions, depending on their energy. This result stems from the unprecedented combination of uniquely resolved measurements and first-principles numerical simulations that reveal the mechanisms responsible for the nondiffusive transport. The transport regime is determined by the interaction of the suprathermal ion orbits with the turbulent plasma dynamics, and is strongly affected by the ratio of the suprathermal ion energy to the background plasma temperature.
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Affiliation(s)
- A Bovet
- École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne, Switzerland
| | - A Fasoli
- École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne, Switzerland
| | - P Ricci
- École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne, Switzerland
| | - I Furno
- École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne, Switzerland
| | - K Gustafson
- École Polytechnique Fédérale de Lausanne (EPFL), Laboratory of Computational Systems Biology, Institute of Bioengineering, School of Life Sciences, CH-1015 Lausanne, Switzerland
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Bovet A, Fasoli A, Furno I. Time-Resolved Measurements of Suprathermal Ion Transport Induced by Intermittent Plasma Blob Filaments. PHYSICAL REVIEW LETTERS 2014; 113:225001. [PMID: 25494075 DOI: 10.1103/physrevlett.113.225001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Indexed: 06/04/2023]
Abstract
Suprathermal ion turbulent transport in magnetized plasmas is generally nondiffusive, ranging from subdiffusive to superdiffusive depending on the interplay of the turbulent structures and the suprathermal ion orbits. Here, we present time-resolved measurements of the cross-field suprathermal ion transport in a toroidal magnetized turbulent plasma. Measurements in the superdiffusive regime are characterized by a higher intermittency than in the subdiffusive regime. Using conditional averaging, we show that, when the transport is superdiffusive, suprathermal ions are transported by intermittent field-elongated turbulent structures that are radially propagating.
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Affiliation(s)
- A Bovet
- École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne, Switzerland
| | - A Fasoli
- École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne, Switzerland
| | - I Furno
- École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne, Switzerland
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Theiler C, Furno I, Loizu J, Fasoli A. Convective cells and blob control in a simple magnetized plasma. PHYSICAL REVIEW LETTERS 2012; 108:065005. [PMID: 22401080 DOI: 10.1103/physrevlett.108.065005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Indexed: 05/31/2023]
Abstract
Blob control by creating convective cells using biased electrodes is demonstrated in simple magnetized toroidal plasmas. A two-dimensional array of electrodes is installed on a metal limiter to obtain different biasing schemes. Detailed two-dimensional measurements across the magnetic field reveal the formation of a convective cell, which shows a high degree of uniformity along the magnetic field. Depending on the biasing scheme, radial and vertical blob velocities can be varied significantly. A high level of cross-field currents limits the achievable potential variations to values well below the applied bias voltage. Furthermore, the strongest potential variations are not induced along the biased flux tube, but at a position shifted in the direction of plasma flows.
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Affiliation(s)
- C Theiler
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confédération Suisse, Lausanne, Switzerland
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