The measured plasma temperature of Ar hollow cathode discharge for several metal cathodes are about 620 ~ 780K at discharge current of 7 ~ 10mA. The optogalvanic signals were measured using hollow cathode discharge tube with argon as buffer gas at change of discharge currents. A change of ionization rate due to electron collision causes an increase or decrease of the electric conductivity. This change in electric conductivity generates the optogalvanic signal. We conclude that optogalvanic signal has close relation with the lowest metastable atoms density at low current.
목차
Abstract 1. 서론 2. 실험 3. 결과 및 고찰 3-1. 플라즈마 온도 측정 3-2. 플라즈마의 균일성 측정 3-3. 플라즈마 밀도 측정 4. 결론 참고문헌