Implementation of ultraviolet Thomson scattering on SG-III laser facility

• Published in: Review of Scientific Instruments
• Main Authors: Zhao, Hang, Li, Zhichao, Yang, Dong, Jiang, Xiaohua, Liu, Yonggang, Wang, Fang, Zhou, Wei, Yan, Yadong, He, Junhua, Li, Sanwei, Guo, Liang, Peng, Xiaoshi, Xu, Tao, Liu, Shenye, Wang, Feng, Yang, Jiamin, Jiang, Shaoen, Zheng, Wanguo, Zhang, Baohan, Ding, Yongkun
• Format: Report
• Language: English
• Published: American Institute of Physics Inc. 2018
• Subjects: Electron-temperature; Plasmas; Beam; North Pole
• Online Access: http://ir.opt.ac.cn/handle/181661/30654; https://doi.org/10.1063/1.5046837

An ultraviolet Thomson-scattering system has been designed and implemented on the Shenguang-III laser facility, a 48-beam, 3ω (351 nm), 180 kJ-level laser driver for high energy density physics and inertial confinement fusion researches. The 4ω (263.3 nm) probe beam of the Thomson-scattering system is injected from the north pole (top) of the target chamber, with an assistant beam-pointing monitor to achieve high pointing accuracy. The Thomson-scattered light is collected by a double-Cassegrain optical transmission system, which provides an achromatic image over a wide wavelength range of 200-800 nm. A novel on-line alignment method is developed and applied to the diagnostic system, ensuring a volumetric positioning accuracy of ∼30 μm for the scattering volume. An online calibration is also conducted to provide the wavelength benchmark and the spectral resolution of the system. This Thomson-scattering system has been tested in a complicated experimental environment with gas-filled hohlraums, and a high-quality ion feature of the scattered light has been obtained. © 2018 Author(s).