Experimental results of a magnetic field modification to the radio frequency driver of a negative ion source

作     者：谢俊炜 谢亚红 韦江龙 梁立振 彭旭峰 杨宇雯 顾玉明 胡纯栋 谢远来 Junwei XIE;Yahong XIE;Jianglong WEI;Lizhen LIANG;Xufeng PENG;Yuwen YANG;Yuming GU;Chundong HU;Yuanlai XIE

作者机构：Institute of Plasma PhysicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of ChinaHefei 230026People’s Republic of China 

出 版 物：《Plasma Science and Technology》 (等离子体科学和技术（英文版）)

年 卷 期：2024年第26卷第4期

页      面：162-167页

核心收录：

学科分类：08[工学] 082701[工学-核能科学与工程] 0827[工学-核科学与技术] 

基　　金：supported by the Comprehensive Research Facility for Fusion Technology Program of China(No.2018-000052-73-01-001228) National Natural Science Foundation of China(No.11975264) 

主　　题：neutral beam injection negative ion source magnetic filter radio frequency ion source 

摘      要：A magnetic field produced by a current flowing through the plasma grid(PG) is one of the solutions to reduce the collisional loss of negative ions in a negative ion source, which reduces the electron temperature in front of the PG. However, the magnetic field diffused into the driver has some influence on the plasma outflowing. In order to investigate the effect of changing this magnetic field on the outflowing of plasma from the driver, a circular ring(absorber) of high permeability iron has been introduced at the driver exit, which can reduce the magnetic field around it and improve plasma outflowing. With the application of the absorber, the electron density is increased by about 35%, and the extraction current measured from the extraction grid is increased from 1.02 A to 1.29 A. The results of the extraction experiment with cesium injection show that both the extraction grid(EG) current and H-current are increased when the absorber is introduced.