Nuclear Techniques ›› 2015, Vol. 38 ›› Issue (7): 70603-070603.

• NUCLEAR ENERGY SCIENCE AND ENGINEERING •

Absolute intensity calibration of the charge exchange recombination spectroscopy system on EAST

ZHANG Yi1,2 LI Yingying2 FU Jia2 YIN Xianghui1,2 LYU Bo2 WANG Qiuping4 YU Yi1 SHI Yuejiang1,3 YE Minyou1

1. 1(School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026, China) 2(Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China) 3(Department of Nuclear Engineering, Seoul National University, Seoul, 151-742, Korea) 4(National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China)
• Received:2015-03-26 Revised:2015-04-17 Online:2015-07-10 Published:2015-07-10

Abstract: Background: The toroidal charge exchange recombination spectroscopy (CXRS) diagnostic was recently deployed on Experimental Advanced Superconducting Tokamak (EAST). The main purpose of this diagnostic system is the profiles of plasma temperature and velocity profiles. The system was calibrated preliminarily by using an integrating sphere lamp whose wavelength and intensity was checked precisely by the manufacturer. As the integrating sphere lamp can only be used before or after the experiment, the real time calibration for the CXRS diagnostic system becomes very important. Purpose: This study aims to use CXRS to measure impurity density, which requires the absolute intensity of the spectrum, so the system must be absolutely calibrated. Methods: The intensity of bremsstrahlung emitted from the plasma during the CXRS experiments was measured. Theoretical computations were performed using relevant parameters of EAST plasma. Results: Compared the measurement results of bremsstrahlung intensity to the theoretical calculation whose parameters were provided by other diagnostic systems, it is shown that errors were in the same order of magnitude and very common in the plasma diagnostic. Conclusion: The experimental results showed that absolute intensity calibration based on the bremsstrahlung is feasible and it gives a possible way for the real time calibration. In the future experiment, the CXRS diagnostic system will adopt this method.