Observation of plasma dynamics in a theta pinch by a novel method  

作　　者：Zhao Wang Rui Cheng Guodong Wang Xuejian Jin Yong Tang Yanhong Chen Zexian Zhou Lulin Shi Yuyu Wang Yu Lei Xiaoxia Wu Jie Yang 

机构地区：[1]Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Advanced Energy Science and Technology Guangdong Laboratory,Huizhou 516003,China [4]College of Physics and Electronic Engineering,Northwest Normal University,Lanzhou 730070,China

出　　处：《Matter and Radiation at Extremes》2023年第4期28-36,共9页极端条件下的物质与辐射（英文）

基　　金：supported by the State Key Development Program for Basic Research of China(Grant No.2022YFA1602503);the National Natural Science Foundation of China(Grant Nos.12120101005 and 11775278).

摘　　要：A novel experimental method is proposed for observing plasma dynamics subjected to magnetic fields based on a newly developed cylindrical theta-pinch device.By measuring simultaneously the temporal profiles of multiple parameters including the drive current,luminosity,plasma density,and plasma temperature,it provides a basis for observing the plasma dynamics of the theta pinch,such as shock transport and magnetohydrodynamic instability.We show that the plasma evolution can be distinguished as three phases.First,in the radial implosion phase,the trajectories of the current sheath and shock wave are ascertained by combining experimental data with a snowplow model(Lee model)in a self-consistent way.Second,in the axial flow phase,we demonstrate that m=0(sausage)instability associated with the plasma axial flow suppresses the plasma end-loss.Third,in the newly observed anomalous heating phase,the lower-hybrid-drift instability may develop near the current sheath,which induces anomalous resistivity and enhanced plasma heating.The present experimental data and novel method offer better understanding of plasma dynamics in the presence of magnetic fields,thereby providing important support for relevant research in magneto-inertial fusion.

关 键 词：DYNAMICS thereby CYLINDRICAL 

分 类 号：O53[理学—等离子体物理]