First experiments on plasma production using field-aligned ICRF fast wave antennas in the large helical device

Nuclear Fushion

article

S. Kamio¹  V.E. Moiseenko²  Yu.V. Kovtun²  H. Kasahara¹  K. Saito¹  R. Seki¹  M. Kanda¹  G. Nomura¹  T. Seki¹  Y. Takemura¹  T. Wauters⁴  R. Brakel⁵  A. Dinklage⁵  D. Hartmann⁵  H. Laqua⁵  T. Stange⁵  A. Alonso⁶  S. Lazerson⁵  Ye. Kazakov⁴  J. Ongena⁴  H. Thomsen⁵  G. Fuchert⁵  I.E. Garkusha² 

[1] National Institute for Fusion Science;Institute of Plasma Physics of the National Science Center ‘Kharkiv Institute of Physics and Technology’;The Graduate University for Advanced Studies;Laboratory for Plasma Physics;Max-Planck-Institut für Plasmaphysik;Laboratorio Nacional de Fusion

关键词: radio-frequency heating;    plasma production;    stellarator;   

DOI  :  10.1088/1741-4326/ac277b

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

The results of the first experimental series to produce a plasma using the ion cyclotron range of frequency (ICRF) in the large helical device (LHD) within the minority scenario developed at Uragan-2M (U-2M) are presented. The motivation of this study is to provide plasma creation in conditions when an electron cyclotron resonance heating start-up is not possible, and in this way widen the operational frame of helical machines. The major constraint of the experiments is the low RF power to reduce the possibility of arcing. No dangerous voltage increase at the radio-frequency (RF) system elements and no arcing has been detected. As a result, a low plasma density is obtained and the antenna-plasma coupling is not optimal. However, such plasmas are sufficient to be used as targets for further neutral beam injection (NBI) heating. This will open possibilities to explore new regimes of operation at LHD and Wendelstein 7-X (W7-X) stellarator. The successful RF plasma production in LHD in this experimental series stimulates the planning of further studies of ICRF plasma production aimed at increasing plasma density and temperature within the ICRF minority scenario as well as investigating the plasma prolongation by NBI heating.

【 授权许可】

Unknown