%0 Journal Article
%T Experimental characteristics of a lower hybrid wave multi-junction coupler in the HT-7 tokamak
%A Ding Bo-Jiang
%A Shan Jia-Fang
%A Liu Fu-Kun
%A Fang Yu-De
%A Wei Wei
%A Wu Zhen-Wei
%A Chen Zhong-Yong
%A Xu Han-Dong
%A Wang Mao
%A Jiang Min
%A Zhang Gong-Rang
%A Huang Feng
%A Zhao Yan-Ping
%A Kuang Guang-Li
%A HT- team
%A <br>丁伯江
%A 单家方
%A 刘甫坤
%A 方瑜德
%A 韦 维
%A 吴振伟
%A 陈忠勇
%A 徐汉东
%A 王 茂
%A 蒋 敏
%A 张公让
%A 黄 峰
%A 赵燕平
%A 匡光力
%A HT- team
%J 中国物理 B
%D 2006
%I 
%X A phase-controlled lower hybrid wave (LHW) multi-junction (MJ) coupler (3(rows)×(columns)× (subwaveguides)) has been developed in the HT-7 tokamak. Simulations show that it is more effective for driving plasma current than an ordinary phase-controlled LHW antenna (3(rows)×12(columns)) (traditional coupler). The plasma--wave coupling experiments show that the reflection coefficient (RC) is below 10%, implying that the MJ grill can launch the wave into the plasma effectively. The effect of power spectrum launched by the MJ coupler on RC indicates that an optimal condition is requisite for a better coupling in the lower hybrid current drive (LHCD) experiments. Studies indicate that the drive efficiency of the MJ antenna is higher than that of the traditional one, which is mainly ascribed to the discrepancy in impurity concentration, plasma temperature, and spectrum directivity. An improved confinement with an electron internal transport barrier is obtained by LHCD. The analysis shows that the modified negative (low) magnetic shear and the change of radial electric field profile due to LHCD are possible factors responsible for the eITB formation.
%K antenna
%K plasma heating
%K plasma confinement<br>天线
%K 等离子加热
%K 等离子禁闭
%K 多结连接
%K 理论物理
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=CD8D6A6897B9334F09D8D1648C376FB4&aid=FC9312F77422C426A67995DF42306CF9&yid=37904DC365DD7266&vid=23CCDDCD68FFCC2F&iid=59906B3B2830C2C5&sid=2E4798C3FF42CDE2&eid=65BB113878CA8F40&journal_id=1009-1963&journal_name=中国物理&referenced_num=0&reference_num=53