Thomson scattering diagnostic system for the XuanLong-50 experiment

H Y Li; S J Li; Q F Xie; J H Liu; R H Bai; R Y Tao; X C Lun; N Li; X K Bo; C Q Liu; L Han; B H Deng

doi:10.1063/5.0088785

Thomson scattering diagnostic system for the XuanLong-50 experiment

Rev Sci Instrum. 2022 May 1;93(5):053504. doi: 10.1063/5.0088785.

Authors

H Y Li¹, S J Li¹, Q F Xie¹, J H Liu¹, R H Bai¹, R Y Tao¹, X C Lun¹, N Li¹, X K Bo¹, C Q Liu¹, L Han¹, B H Deng¹

Affiliation

¹ Hebei Key Laboratory of Compact Fusion, Langfang 065001, China.

PMID: 35649791
DOI: 10.1063/5.0088785

Abstract

A 15-point Thomson scattering diagnostic system is developed for ENN's spherical torus experiment XuanLong-50 (EXL-50). A BeamTech laser with 3 J/pulse (1064 nm wavelength) at 50 Hz repetition rate is chosen for measurements during EXL-50 plasma operations. To enable measurements at low density (∼0.5 × 10¹⁸ m^-3) plasma operations, the opto-mechanical subsystems are carefully designed to maximize the collection and transmission of the scattered light and to minimize the stray light level. In addition, the high bandwidth trans-impedance amplifiers and segmented high speed waveform digitizers allow for the application of muti-pulse averaging to further improve the signal-to-noise ratio. Details of the diagnostic system are described and initial experimental results are presented.