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Generation of energetic electrons by an electron cyclotron wave through stochastic heating in a spherical tokamak

Published online by Cambridge University Press:  28 November 2023

Mingyuan Wang
Affiliation:
School of Mathematics and Physics, Anqing Normal University, Anqing 246133, PR China Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Shikui Cheng
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Bing Liu
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Shaodong Song
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Dong Guo
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Yunyang Song
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Wenjun Liu
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Debabrata Banerjee
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Songjian Li
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Tiantian Sun
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Xiang Gu
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Yingying Li
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Jiaqi Dong
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Yuejiang Shi*
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Y.-K. Martin Peng
Affiliation:
Hebei Key Laboratory of Compact Fusion, Langfang 065001, PR China ENN Science and Technology Development Co., Ltd., Langfang 065001, PR China
Adi Liu*
Affiliation:
Department of Plasma Physics and Fusion Engineering, University of Science and Technology of China, Hefei, Anhui 230026, PR China
*
Email addresses for correspondence: yjshi@ipp.ac.cn, lad@ustc.edu.cn
Email addresses for correspondence: yjshi@ipp.ac.cn, lad@ustc.edu.cn

Abstract

This study presents novel findings on stochastic electron heating via a random electron cyclotron wave (ECW) in a spherical tokamak. Hard x ray measurements demonstrate the time evolution of hard x ray counts at different energy bands, consistent with predictions from the stochastic heating model. The ECW heating rate shows a positive correlation with applied power, confirming the effectiveness of stochastic heating. Remarkably, the ECW-driven plasma current remains insensitive to ECW incidence angle, consistent with model predictions. The observed stochastic heating of electrons offers potential for exploring innovative non-inductive current drive modes in spherical tokamaks. This research contributes to the understanding of plasma behaviour and motivates the development of new models for non-inductive current drive in fusion devices.

Type
Research Article
Copyright
Copyright © The Author(s), 2023. Published by Cambridge University Press

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