High proton ratio plasma production in a small negative ion source
High proton ratio plasma production in a small negative ion source
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在小型负离子源中产生高质子比等离子体
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
T. Imai
中科院分区：
文献类型：
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作者：
T. Morishita;T. Inoue;T. Iga;Kazuhiro Watanabe;T. Imai
在小型(1.4L)电弧放电多尖点源中在1.4Pa的压力下测量质子比。在引出的正离子束中测量的质子比为50％。通过在源中应用横向磁场作为磁过滤器，即使在如此小的源中，质子比也急剧增加到 90%。为了阐明质子产生过程，对耦合速率方程进行了数值求解，以估计不同尺寸离子源中的粒子（H+、H2+、H3+ 和 H0）密度。已经明确的是，主要的质子生产过程随源尺寸的不同而不同。在对源等离子体有更好限制的大尺寸源中，H原子的电离对于增加质子产率变得有效。在小离子源中，H2+ (H2++e→H++H+e)的解离是质子产生的主要过程。通过在小源中采用磁性过滤器，在提取区域中抑制了由一次电子碰撞产生的H2+。分子离子是...
A proton ratio was measured in the small (1.4 l) arc discharge multicusp source at a pressure of 1.4 Pa. A measured proton ratio in an extracted positive ion beam was 50%. By applying the transverse magnetic field as the magnetic filter in the source, the proton ratio drastically increased to 90% even in such a small source. To clarify the proton production processes, coupled rate equations were numerically solved to estimate particle (H+, H2+, H3+, and H0) densities in the various size of ion source. It has been clarified that a main proton production process is different with the source size. In the large size source, which has better confinement of the source plasma, the ionization of H atom becomes effective to increase the proton yield. In the small ion source, the dissociation of H2+ (H2++e→H++H+e) is the dominant process for the proton production. By adopting the magnetic filter in the small source, H2+ production by primary electron impact is suppressed in the extraction region. Molecular ions are...