Characteristics of the extracted negative-ion beam in a cesium-free negative-ion source using TPDsheet-U
Characteristics of the extracted negative-ion beam in a cesium-free negative-ion source using TPDsheet-U
复制标题
使用 TPDsheet-U 在无铯负离子源中提取的负离子束的特性
DOI：
10.1088/1741-4326/ac21fa
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发表时间：
2021
期刊：
影响因子：
3.3
通讯作者：
Kawamura K.
中科院分区：
文献类型：
--
作者：
Tonegawa A.;Kaminaga H.;Hanai K.;Takimoto T.;Sato K.N.;Kawamura K.
报道了在磁化片状等离子体装置（TPDsheet-U）上实现高性能无铯负离子源的进展。在实验中，使用单孔/多孔网格成功地从片状等离子体中提取了H−离子。单孔栅实验结果表明，TPD sheet-U中无铯H−离子束的负氢离子流密度（JC（H−））性能约为ITER负离子中性束注入器（NNBI）中含铯H−离子源的1/4。(i)在引出电压为10 kV、放电电流Id为90 A、气压为0.3 Pa的条件下，JC（H-）为≤ 7.5 mA cm-2。(ii)使用这种软磁过滤器（SMF）的电子电流J EG（e）仅为不使用SMF的电子电流的10%;对于I d= 50 A和外部磁场强度为38 mT的单孔栅极，在y< 18 mm时J EG（e）/J C（H−）比降低到0.4以下。
The progress toward realizing a high-performance cesium (Cs)-free negative-ion source based on volume production in a magnetized sheet plasma device (TPDsheet-U) is reported. In the experiments, H− ions were successfully extracted from sheet plasma using single-/multi-aperture grids. The experimental results of the single-aperture grid show that the negative hydrogen ion current density (J C (H−)) performance of Cs-free H− ion beams in TPDsheet-U is about one-fourth that of Cs-containing H− ion sources in the ITER negative-ion neutral-beam injector (NNBI).(i) The J C (H−) was∼ 7.5 mA cm− 2 at an extraction voltage of 10 kV, a discharge current I d of 90 A, and a gas pressure of 0.3 Pa.(ii) The electron current J EG (e) with this soft magnetic filter (SMF) was only∼ 10% of the electron current without the SMF; The J EG (e)/J C (H−) ratio was reduced below 0.4 at y< 18 mm for a single-aperture grid with the SMF at I d= 50 A and external magnetic field strength of 38 mT.