[17p-C204-1~20] 8.1 Plasma production and diagnostics

△ [17p-C204-2] Measurement of the Degree of Ionization in a Helium ECR Discharge in a Simple Cusp Field using the Line Intensity Ratio Method

〇(M1)Akira Ueda¹, Taiichi Shikama¹, Tatsuya Teramoto¹, Takanori Higashi¹, Yohei Iida², Masahiro Hasuo¹ (1.Kyoto Univ., 2.Bunkokeiki)

Keywords:ECR plasma, collisional radiative model, the degree of ionization

It has been reported that the high degree of ionization could be obtained in a ECR discharge in a simple cusp field which constitutes minimum-B configuration. In this research, we have revealed the degree of ionization in a helium plasma. We determined the radial distribution of the electron and the ground state atom densities using measurement of HeI emission line intensities and collisional-radiative model analysis, and evaluated the degree of ionization from these values. As the result, the degree of ionization reaches more than 20 % inside the ECR surface.