Measurement of electron temperature fluctuations on J-TEXT via correlation ECE

H Zhou; Z J Yang; X L Xie; C Zhang; X M Pan; Q X Cai; B W Ruan

doi:10.1063/1.5035121

Measurement of electron temperature fluctuations on J-TEXT via correlation ECE

Rev Sci Instrum. 2018 Oct;89(10):10H105. doi: 10.1063/1.5035121.

Authors

H Zhou¹, Z J Yang¹, X L Xie¹, C Zhang¹, X M Pan¹, Q X Cai¹, B W Ruan¹

Affiliation

¹ International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics, State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.

PMID: 30399888
DOI: 10.1063/1.5035121

Abstract

The capabilities of the joint-Texas experimental tokamak correlation electron cyclotron emission (CECE) diagnostic have recently been extended with an upgrade. Four new yttrium iron garnet (YIG) filters from 4 GHz to 18 GHz with a bandwidth of 90 ∼ 230 MHz are added to the previous 4 channels. Optical optimization of the transmission line has improved the poloidal resolution, which allows k _θ < 3.08 cm^-1. The improvement of video amplifiers allows the frequency and amplitude gain to be adjusted discretely from 200 kHz to 1 MHz and from 200 to 1000, respectively, for different situations. A controller is designed to remotely adjust the center frequency of the YIG filters. Based on the CECE, the distribution and the effect of magnetohydrodynamic instabilities on electron temperature fluctuations have been observed. The experiment results show good performance of the upgraded CECE diagnostic.