Observation of helical m/n=1/1 saturated steady mode in EAST pure electron heating scenario with q(0) <= 1

doi:10.1088/1741-4326/abadab

	Observation of helical m/n=1/1 saturated steady mode in EAST pure electron heating scenario with q(0) <= 1
	Xu, Liqing; Li, Erzhong; Zhou, Tianfu; Duan, Yanmin; Huang, Yueheng; Lian, Hui; Wang, Shouxin; Liu, Jianwen; Chao, Yan; Zang, Qing
刊名	NUCLEAR FUSION
	2020-10-01
卷号	60
关键词	MHD helical kink mode nonlinear simulation tokamak diagnostic EAST tokamak
ISSN号	0029-5515
DOI	10.1088/1741-4326/abadab
通讯作者	Li, Erzhong(rzhonglee@ipp.cas.cn)
英文摘要	We observed for the first time a helical m/n = 1/1 (mis the poloidal mode number andnis the toroidal mode number) saturated steady mode (SSM) in the center of the EAST electron heating dominant plasma where the core safety factor was close to but slightly below unity and the T-e profile had an extreme peak at the plasma center ( T-e is the electron temperature). An internal crash can be caused by the dynamics of the SSM, and its influence on the electron temperature profile is as large as that of a typical sawtooth crash (SC) in magnitude. Due to the weak magnetic shear in the core, the SSM regularly exhibits an m/n = 2/2 harmonic component. For low shear q <= 1 auxiliary heated plasma, the SSM cannot cause the degradation of plasma confinement (beta(p) T-e), but an SC is indeed a harmful factor. Three-dimensional resistive magnetohydrodynamic simulations with a realistic EAST strong elongated magnetic configuration, a high Lundquist number (S = 10(8)) and a strong central peaked pressure profile, have been made to demonstrate the formation of the SSM in the case of q(0) <= 1 and the destabilization of the SC in another case with q(0) < 1. These nonlinear simulation results agree well with the observations of both the SSM and SC in EAST electron heating dominant discharges with an extreme central peaked T-e. An M3D simulation found that the SC is caused by additional newly developed harmonics of the m/n = 1/1 helical instability. Nonlinear simulation also predicted a modulation of the SSM on current in the plasma core, which is favorable for maintaining q(0) <= 1 in the plasma core. Furthermore, nonlinear simulation also showed that a small toroidal plasma flow can be generated by the SC.
资助项目	National Natural Science Foundation of China[11975273] ; Youth Innovation Promotion Association Chinese Academy of Sciences[2018483]
WOS关键词	EQUILIBRIA
WOS研究方向	Physics
语种	英语
出版者	IOP PUBLISHING LTD
WOS记录号	WOS:000575199300001
资助机构	National Natural Science Foundation of China ; Youth Innovation Promotion Association Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://ir.hfcas.ac.cn:8080/handle/334002/104419]
专题	中国科学院合肥物质科学研究院
通讯作者	Li, Erzhong
作者单位	Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Peoples R China
推荐引用方式 GB/T 7714	Xu, Liqing,Li, Erzhong,Zhou, Tianfu,et al. Observation of helical m/n=1/1 saturated steady mode in EAST pure electron heating scenario with q(0) <= 1[J]. NUCLEAR FUSION,2020,60.
APA	Xu, Liqing.,Li, Erzhong.,Zhou, Tianfu.,Duan, Yanmin.,Huang, Yueheng.,...&Hu, Liqun.(2020).Observation of helical m/n=1/1 saturated steady mode in EAST pure electron heating scenario with q(0) <= 1.NUCLEAR FUSION,60.
MLA	Xu, Liqing,et al."Observation of helical m/n=1/1 saturated steady mode in EAST pure electron heating scenario with q(0) <= 1".NUCLEAR FUSION 60(2020).