Density fluctuation measurements using beam emission spectroscopy on Heliotron J

作者：Kobayashi S^*; Kado S; Oishi T; Ohshima S; Kagawa T; Nagae Y; Yamamoto S; Mizuuchi T; Nagasaki K; Okada H; Minami T; Estrada T; Murakami S; Lee H Y; Minami T; Harada T; Nakamura Y; Konoshima S; Toushi K; Sano F

来源：Review of Scientific Instruments, 2012, 83(10): 10D535.

DOI：10.1063/1.4734039

This paper describes the measurement of the density fluctuation using beam emission spectroscopy in Heliotron J, having the non-symmetrical helical-magnetic-axis configuration. In order to optimize the sightlines, the numerical calculations are carried out to estimate the spatial resolution and the observation location. When a tangential neutral beam is used as diagnostic one, suitable sightlines from the newly installed diagnostic port are selected whose spatial resolution Delta rho is less than +/- 0.07 over the entire plasma region. Modification of the interference filter and the detection systems enables us to measure the radial profile of the density fluctuation. Each of the three coherent modes due to the fast-ion-driven magnetohydrodynamic instabilities has different radial structure of the density fluctuation.

• 出版日期2012-10