Pasqualotto R, Alfier A, Lotto L
Consorzio RFX-Associazione Euratom-Enea sulla Fusione, corso Stati Uniti 4, I-35127 Padova, Italy.
Rev Sci Instrum. 2010 Oct;81(10):10D710. doi: 10.1063/1.3475372.
The rf source test facility SPIDER will test and optimize the source of the 1 MV neutral beam injection systems for ITER. Cavity ring-down spectroscopy (CRDS) will measure the absolute line-of-sight integrated density of negative (H(-) and D(-)) ions, produced in the extraction region of the source. CRDS takes advantage of the photodetachment process: negative ions are converted to neutral hydrogen atoms by electron stripping through absorption of a photon from a laser. The design of this diagnostic is presented with the corresponding simulation of the expected performance. A prototype operated without plasma has provided CRDS reference signals, design validation, and results concerning the signal-to-noise ratio.
射频源测试设施“蜘蛛”（SPIDER）将对国际热核聚变实验堆（ITER）1兆伏中性束注入系统的源进行测试和优化。腔衰荡光谱技术（CRDS）将测量源的引出区域产生的负离子（H⁻和D⁻）的绝对视线积分密度。CRDS利用了光剥离过程：负离子通过吸收激光光子进行电子剥离而转化为中性氢原子。本文介绍了这种诊断方法的设计以及预期性能的相应模拟。一个无等离子体运行的原型提供了CRDS参考信号、设计验证以及关于信噪比的结果。
