Clarification on characteristics of the impurity transport in high-temperature plasmas by using a new tracer-encapsulated solid pellet

• Project/Area Number: 17KK0121
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: National Institute for Fusion Science
• Principal Investigator: Tamura Naoki 核融合科学研究所, ヘリカル研究部, 准教授 (80390631)
• Project Period (FY): 2018 – 2022
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥13,650,000 (Direct Cost: ¥10,500,000、Indirect Cost: ¥3,150,000)
• Keywords: プラズマ・核融合 / 炉心プラズマ / 不純物輸送 / トレーサー内蔵固体ペレット / TESPEL / トレーサー内蔵ペレット

Outline of Final Research Achievements

TESPEL injection experiments have been performed in the W7-X in Germany and the TJ-II in Spain. It was found that TESPEL in W7-X can place impurity tracers inside the plasma better than expected; in addition, comparison with a laser blow-off method revealed that the difference in impurity deposited position has a significant impact on the temporal evolution; spatial distribution of impurities injected into the plasmas. TESPEL also revealed that an extensive range of impurity transport from boron to tungsten could be investigated in W7-X. On the other hand, although preliminary experiments have been conducted in TJ-II, full-scale experiments using the new TESPEL could not be undertaken due to the influence of the novel coronavirus infection.

Academic Significance and Societal Importance of the Research Achievements

本研究で得られた成果として特筆すべき点は、不純物供給位置の違いが磁場閉じ込め高温プラズマ中の不純物の時間発展、つまり空間分布に大きな影響を与えることを明らかにしたことである。このことは、磁場閉じ込め高温プラズマ中の不純物輸送に関して、新たな知見を与えており、その学術的意義は高いと言える。また、将来の核融合炉において不純物発生源はプラズマの中心部と周辺部それぞれにあることから、新たに得られた知見は、それぞれに対して対策が必要であることを強く示唆している。これは、核融合炉の実現の加速化において非常に重要な知見であることから、その社会的意義も高いと言える。

Research Products

• [Int'l Joint Research] エネルギー・環境・科学技術研究センター(スペイン) (2020)
  • Year and Date: 2020-02-29
• [Int'l Joint Research] マックスプランク・プラズマ物理研究所(ドイツ) (2018)
• [Journal Article] Overview of the TJ-II stellarator research programme towards model validation in fusion plasmas (2022)
  • Author(s): C. Hidalgo, E. Ascasibar, U. Losada, S. Ohshima, H. Takahashi 他130名
  • Journal Title: Nuclear Fusion Volume: 62 Issue: 4 Pages: 042025-042025
  • DOI: 10.1088/1741-4326/ac2ca1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Experimental confirmation of efficient island divertor operation and successful neoclassical transport optimization in Wendelstein 7-X (2022)
  • Author(s): Thomas Sunn Pedersen, I. Abramovic, P. Agostinetti, M. Agredano Torres, S. Akaslompolo, J. Alcuson Belloso, P. Aleynikov, K. Aleynikova, M. Alhashimi, A. Ali, N. Allen, A. Alonso, G. Anda, T. Andreeva, C. Angioni, A. Arkhipov, A. Arnold, W. Asad, E. Ascasibar, M.-H. Aumeunier, K. Avramidis, ..., N. Tamura, et al.
  • Journal Title: Nuclear Fusion Volume: 62 Issue: 4 Pages: 042022-042022
  • DOI: 10.1088/1741-4326/ac2cf5
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] The interpretation of magnetic activity associated with pellet injections into plasmas creasted in the stellarator TJ-II (2021)
  • Author(s): K.J. McCarthy, E. Ascasibar, N. Tamura, N. Panadero, I. Garcia-Cortes, B. van Milligen, A. Cappa, R. Garcia, J. Hernandez-Sanchez, M. Liniers, G. Motojima, M. Navarro, I. Pastor and TJ-II team
  • Journal Title: Nuclear Fusion Volume: 61 Issue: 7 Pages: 076014-076014
  • DOI: 10.1088/1741-4326/ac04f6
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] First neutral beam experiments on Wendelstein 7-X (2021)
  • Author(s): Samuel A. Lazerson, Oliver Ford, Simppa Akaslompolo, Sergey Bozhenkov, Christoph Slaby, Lilla Vano, Annabelle Spanier, Paul McNeely, Norbert Rust, Dirk Hartmann, Peter Poloskei, Birger Buttenschoen, Rainer Burhenn, Naoki Tamura, Rene Bussiahn, Thomas Wegner, et al.
  • Journal Title: Nuclear Fusion Volume: 61 Issue: 9 Pages: 096008-096008
  • DOI: 10.1088/1741-4326/ac121c
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Investigation of TESPEL cloud dynamics in Wendelstein 7-X stellarator (2020)
  • Author(s): Kocsis Gabor、Tamura Naoki、Bussiahn Rene、McCarthy Kieran、Baldzuhn J?rgen、Biedermann Christoph、Cseh Gabor、Damm Hannes、Kornejew Petra、K?nig Ralf、Panadero Nerea、Szepesi Tamas
  • Journal Title: Nuclear Fusion Volume: 61 Issue: 1 Pages: 016006-016006
  • DOI: 10.1088/1741-4326/abbc84
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Charge-state independent anomalous transport for a wide range of different impurity species observed at Wendelstein 7-X (2020)
  • Author(s): Langenberg A.、Wegner Th.、Pablant N. A.、Marchuk O.、Geiger B.、Tamura N.、Bussiahn R.、Kubkowska M.、Moll?n A.、Traverso P.、Smith H. M.、Fuchert G.、Bozhenkov S.、Damm H.、Pasch E.、Brunner K.-J.、Knauer J.、Beurskens M.、Burhenn R.、Wolf R. C.、W7-X Team
  • Journal Title: Physics of Plasmas Volume: 27 Issue: 5 Pages: 052510-052510
  • DOI: 10.1063/5.0004462
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Integration of the TESPEL injection system at W7-X (2020)
  • Author(s): Laube Ralph、Bussiahn Rene、Tamura Naoki、McCarthy Kieran J.
  • Journal Title: Fusion Engineering and Design Volume: 150 Pages: 111259-111259
  • DOI: 10.1016/j.fusengdes.2019.111259
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Observation of the TESPEL-injected impurities behaviour by the PHA system at Wendelstein 7-X (2020)
  • Author(s): M. Kubkowska, N. Tamura, A. Chomiczewska, T. Fornal, M. Gruca, N. Krawczyk, S. Jablonski, L. Ryc, R. Bussiahn, K. Brunner, R. Burhenn, J. Knauer, A. Langenberg, U. Neuner, H. Thomsen and the W7-X team
  • Journal Title: Journal of Instrumentation Volume: 15 Pages: 1-7
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Plasma termination by excess pellet fueling and impurity injection in TJ-II, the Large Helical Device and Wendelstein 7-X (2019)
  • Author(s): Dinklage A., McCarthy K.J., Suzuki C., Tamura N., Wegner Th., Yamada H., Baldzuhn J., Brunner K.J., Buttenschoen B., Damm H., Drewelow P., Fuchert G., Hirsch M., Hoefel U., Kasahara H., Knauer J., Maier D., Miyazawa J., Motojima G., Oishi T., Rahbarnia K., Sunn Pedersen T., Sakamoto R., Wolf R.C., Zhang D.
  • Journal Title: Nuclear Fusion Volume: 59 Issue: 7 Pages: 076010-076010
  • DOI: 10.1088/1741-4326/ab17fd
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The impact of fast electrons on pellet injection in the stellarator TJ-II (2018)
  • Author(s): McCarthy K J、Panadero N、Combs S K、Tamura N、Ascas?bar E、Calvo M、Chmyga A、Estrada T、Fontdecaba J M、Garc?a R、Hern?ndez S?nchez J、Khabanov P、Liners M、Melnikov A V、Pastor I、Rojo B、TJ-II team1、LHD experiment group2
  • Journal Title: Plasma Physics and Controlled Fusion Volume: 61 Issue: 1 Pages: 014013-014013
  • DOI: 10.1088/1361-6587/aae038
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Tracer-Encapsulated Solid Pellet (TESPEL) injection system for Wendelstein 7-X (2018)
  • Author(s): Bussiahn R.、Tamura N.、McCarthy K. J.、Burhenn R.、Hayashi H.、Laube R.、Klinger T.、LHD Experiment Group、W7-X Team
  • Journal Title: Review of Scientific Instruments Volume: 89 Issue: 10
  • DOI: 10.1063/1.5038844
  • Peer Reviewed / Int'l Joint Research
• [Presentation] New insights into cryogenic and TESPEL pellet physics in TJ-II (2022)
  • Author(s): D. Medina-Roque, I. Garcia-Cortes, K.J. McCarthy, N. Tamura, N. Panadero, E. Ascasibar, T. Estrada, J. Hernandez-Sanchez, A.S. Kozachek, M. Liniers, P. Medina, M.A. Ochando, J.L. de Pablos, I. Pastor, C. Toledo, B. van Milligen & TJ-II team
  • Organizer: 48th EPS Conference on Plasma Physics
  • Int'l Joint Research
• [Presentation] Impurity transport studies on Wendelstein 7-X by Tracer-Encapsulated Solid Pellets (2021)
  • Author(s): R. Bussiahn, N. Tamura, K.J. McCarthy, T. Andreeva, J. Brunner, B. Buttenschoen, A. Dinklage, B. Geiger, J. Geiger, G. Fuchert, A. Langenberg, N. Pablant, K. Rhabarnia, C. Swee, Th. Wegner and the W7-X team
  • Organizer: 47th EPS Conference on Plasma Physics
  • Int'l Joint Research
• [Presentation] Versatility and Flexibility of the Tracer-Encapsulated Solid Pellet as a Diagnostic Tool in Magnetic Fusion Plasma (2019)
  • Author(s): N. Tamura, R. Bussiahn, K.J. McCarthy
  • Organizer: 3rd European Conference on Plasma Diagnostics
  • Int'l Joint Research / Invited
• [Presentation] Radiation distribution and origin in W7-X (2019)
  • Author(s): D. Zhang
  • Organizer: 9th International workshop on "Stochasticity in Fusion Plasmas (SFP)"
  • Int'l Joint Research / Invited
• [Presentation] Impact of injecting different TESPEL-types on Wendelstein 7-X plasmas (2019)
  • Author(s): R. Bussiahn, N. Tamura, K.J. McCarthy, M. Beurskens, S. Bozhenkov, H. Damm, G. Fuchert, E. Pasch, E. Edlund, M. Porkolab, Z. Huang, L.-G. Boettger, O. Grulke, A. von Stechow, R. Burhenn, B. Buttenschoen, K.J. Brunner, J. Knauer, A. Langenberg, O. Marchuk, N. Pablant, N. Chaudhary, M. Hirsch, U. Hoefel, J.W. Oosterbeek
  • Organizer: 3rd European Conference on Plasma Diagnostics
  • Int'l Joint Research
• [Presentation] Observation of the TESPEL-injected impurities behavior by the PHA system at Wendelstein 7-X (2019)
  • Author(s): Monika Kubkowska, Naoki Tamura, Agata Chomiczewska, Tomasz Fornal, Marta Gruca, Natalia Krawczyk, Slawomir Jablonski, Leszek Ryc, Rene Bussiahn, Rainer Burhenn, Ulrich Neuner, Henning Thomsen and the W7-X team
  • Organizer: 3rd European Conference on Plasma Diagnostics
  • Int'l Joint Research
• [Presentation] First Results from an Event Synchronized - High Repetition Rate Thomson Scattering System at Wendelstein 7-X (2019)
  • Author(s): H. Damm, E. Pasch, J. Baldzuhn, S. Bozhenkov, K.J. Brunner, R. Bussiahn, A. Dinklage, G. Fuchert, N. Tamura, E.R. Scott and the W7-X Team
  • Organizer: 3rd European Conference on Plasma Diagnostics
  • Int'l Joint Research
• [Presentation] Impurity Transport Studies using TESPEL in W7-X stellarator (2019)
  • Author(s): N. Tamura, R. Bussiahn, K.J. McCarthy, B. Buttenschoen, M. Kubkowska, N. Pablant, A. Langenberg, D. Zhang, Th. Wegner, R. Burhenn and the W7-X team
  • Organizer: 46th EPS Conference on Plasma Physics
  • Int'l Joint Research
• [Presentation] Investigation of TESPEL cloud dynamics in Wendelstein 7-X stellarator (2019)
  • Author(s): G. Kocsis, N. Tamura, R. Bussiahn, K.J. McCarthy, J. Baldzuhn, C. Biedermann, G. Cseh, H. Damm, N. Panadero, T. Szepesi and the W7-X Team
  • Organizer: 46th EPS Conference on Plasma Physics
  • Int'l Joint Research
• [Presentation] 1-dim Collisional Radiative impurity transport code with internal particle source for TESPEL injection experiments in RFX-mod2 (2019)
  • Author(s): L.Carraro, P. Innocente, N.Tamura
  • Organizer: 46th EPS Conference on Plasma Physics
  • Int'l Joint Research
• [Presentation] Diffusion Dominated Transport for a Wide Range of Different Impurity Species Observed at Wendelstein 7-X (2019)
  • Author(s): A. Langenberg, Th. Wegner, B. Geiger, A. Mollen, H.M. Smith, O. Marchuk, R. Bussiahn, N. Tamura, N.A. Pablant, P. Traverso, B. Buttenschoen, R. Burhenn, M. Beurskens, R.C. Wolf and the W7-X Team
  • Organizer: 46th EPS Conference on Plasma Physics
  • Int'l Joint Research
• [Presentation] Tracer-filled pellets for performing impurity transport studies in magnetically-confined plasmas of stellarators (2019)
  • Author(s): K. J. McCarthy, N. Tamura, R. Bussiahn, I. Garcia-Cortes, J. Hernandez Sanchez and N. Panadero
  • Organizer: XXXVII Reunion Bienal de la Real Sociedad Espanola de Fisica
• [Presentation] Pulse Height Analysis diagnostic for impurity behavior studies at W7-X (2019)
  • Author(s): Monika Kubkowska for the W7-X team
  • Organizer: PLASMA-2019
  • Int'l Joint Research / Invited
• [Presentation] Impurity Transport Studies using TESPEL in stellarators: A comparison between TJ-II, W7-X and LHD (2019)
  • Author(s): N. Tamura
  • Organizer: 22nd International Stellarator & Heliotron Workshop
  • Int'l Joint Research / Invited
• [Presentation] TURBULENCE STUDIES BY THE PHASE CONTRAST IMAGING DIAGNOSTIC IN THE WENDELSTEIN 7-X STELLARATOR (2019)
  • Author(s): Z. Huang
  • Organizer: 22nd International Stellarator & Heliotron Workshop
  • Int'l Joint Research
• [Presentation] Impact of the Tracer-Encapsulated Solid Pellets (TESPEL) on Wendelstein 7-X plasmas (2019)
  • Author(s): R. Bussiahn, N. Tamura, K.J. McCarthy, C. Brandt, K.J. Brunner, R. Burhenn, B. Buttenschon, H. Damm, G. Kocsis, A. Langenberg, N. Pablant, A. v. Stechow, P. Traverso, Th. Wegner, D. Zhang, the LHD experiment group and the W7-X team
  • Organizer: DPG Spring Meeting 2019
• [Presentation] Dynamics of TESPEL injections in the W7-X stellarator observed with SXR tomography (2019)
  • Author(s): C. Brandt, J. Schilling, H. Thomsen, R. Bussiahn, N. Tamura, R. Burhenn, and the Wendelstein 7-X Team
  • Organizer: DPG Spring Meeting 2019
• [Presentation] Tracer-Encapsulated Solid Pellet (TESPEL) Injection System for Wendelstein 7-X (2018)
  • Author(s): Tamura N.、Bussiahn R.、McCarthy K. J.、Burhenn R.、Hayashi H.、Laube R.、Klinger T.、LHD Experiment Group、W7-X Team
  • Organizer: 22nd Topical Conference on High-Temperature Plasma Diagnostics
  • Int'l Joint Research
• [Presentation] Integration of the TESPEL injection system at W7-X (2018)
  • Author(s): Laube, Ralph; Bussiahn, Rene; Tamura, Naoki
  • Organizer: 30TH SYMPOSIUM ON FUSION TECHNOLOGY
  • Int'l Joint Research
• [Presentation] Development and Initial Results of a Tracer-Encapsulated Solid Pellet (TESPEL) Injection System on Wendelstein 7-X (2018)
  • Author(s): R. Bussiahn, N. Tamura, K.J. McCarthy, R. Burhenn, H. Hayashi, R. Laube, T. Klinger1, the LHD experiment group and the W7-X team
  • Organizer: 2nd Asia-Pacific Conference on Plasma Physics
  • Int'l Joint Research
• [Presentation] TESPEL injection experiment in TJ-II (2018)
  • Author(s): N. Tamura, K.J. McCarthy, N. Panadero, E. Ascasibar, E. Pawelec, A. Chmyga, T. Estrada, J.M. Fontdecaba, R. Garcia, J. Hernandez Sanchez, P. Khabanov, M. Liners, A. V. Melnikov, I. Pastor, B. Rojo, TJ-II team, and LHD experiment group
  • Organizer: 第35回プラズマ・核融合学会年会
• [Remarks] Hollowing out pearls with watchmaker's tools
  • URL: https://euro-fusion.org/eurofusion-news/hollowing-out-pearls-with-watchmakers-tools/
• [Remarks] Tracer pellets
  • URL: https://www.ipp.mpg.de/5029547/tespel
• [Remarks] Impuritry Pellet Injector (TESPEL)
  • URL: https://www.ipp.mpg.de/4622349/TESPEL
• [Remarks] Hollowing out pearls with watchmaker's tools
  • URL: https://www.euro-fusion.org/news/2021/february/hollowing-out-pearls-with-watchmakers-tools/