Testing of a pulsed He supersonic beam for plasma edge diagnostic in the TJ-IU torsatron
Testing of a pulsed He supersonic beam for plasma edge diagnostic in the TJ-IU torsatron
复制标题
在 TJ-IU torsatron 中测试用于等离子体边缘诊断的脉冲氦超音速束
DOI：
10.1016/s0022-3115(97)80225-5
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发表时间：
1997
影响因子：
3.1
通讯作者：
I. Tanarro
中科院分区：
文献类型：
--
作者：
F. Tabarés;D. Tafalla;V. Herrero;I. Tanarro
一种基于氦超音速膨胀的新型紧凑原子束源已开发出来，可用作等离子体边缘诊断。光束由脉冲阀产生，持续时间在 0.2 至 2 毫秒之间，标称重复率 < 500 Hz。在低于 2 bar 的停滞压力下，可以实现 > 10 的终端速比和 ± 1° 的发散度。据我们所知，该诊断已在 TJ-IU torsatron 上的 ECRH 等离子体中进行了测试，这代表着超声束在等离子体表征中的首次应用。选择最小化注入等离子体的 He 总量的操作条件。在局部 He 密度为 ⋍ 1 × 1011cm−3 且光束直径 < 1 cm 时，可以获得低密度等离子体的非微扰注入条件。由于 ECRH 等离子体的电子密度相对较低，并且超音速 He 束具有良好的穿透特性，因此诊断可用于相当低的归一化等离子体短半径 r a (a = 12 cm) 值。介绍了原子束诊断优化的详细信息以及 TJ-IU 等离子体稳态条件的典型结果。
A new, compact atomic beam source based on the supersonic expansion of He has been developed for application as a plasma edge diagnostic. The beam is produced from a pulsed valve with a duration between 0.2 to 2 ms and a nominal repetition rate < 500 Hz. A terminal speed ratio > 10 and a divergence of ± 1° have been achieved at stagnation pressures below 2 bar. The diagnostic has been tested in ECRH plasmas on the TJ-IU torsatron, representing the first application of a supersonic beam to plasma characterization, to our knowledge. Operational conditions which minimized the total amount of He injected into the plasma were chosen. Non-perturbative injection conditions in the low density plasmas could be obtained at local He densities of ⋍ 1 × 1011cm−3and a beam diameter < 1 cm. Due to the relatively low electron density of the ECRH plasmas, and to the good penetration characteristics of the supersonic He beam, the diagnostic could be used up to fairly low values of the normalized plasma minor radius, r a (a = 12 cm) . Details of the optimization of the atomic beam diagnostics and typical results for steady state conditions in the TJ-IU plasmas are presented.