skip to main content

SciTech ConnectSciTech Connect

Title: The circuit of polychromator for Experimental Advanced Superconducting Tokamak edge Thomson scattering diagnostic

The detector circuit is the core component of filter polychromator which is used for scattering light analysis in Thomson scattering diagnostic, and is responsible for the precision and stability of a system. High signal-to-noise and stability are primary requirements for the diagnostic. Recently, an upgraded detector circuit for weak light detecting in Experimental Advanced Superconducting Tokamak (EAST) edge Thomson scattering system has been designed, which can be used for the measurement of large electron temperature (T{sub e}) gradient and low electron density (n{sub e}). In this new circuit, a thermoelectric-cooled avalanche photodiode with the aid circuit is involved for increasing stability and enhancing signal-to-noise ratio (SNR), especially the circuit will never be influenced by ambient temperature. These features are expected to improve the accuracy of EAST Thomson diagnostic dramatically. Related mechanical construction of the circuit is redesigned as well for heat-sinking and installation. All parameters are optimized, and SNR is dramatically improved. The number of minimum detectable photons is only 10.
Authors:
; ; ;  [1] ;  [2]
  1. Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031 (China)
  2. General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)
Publication Date:
OSTI Identifier:
22220345
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 84; Journal Issue: 9; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCURACY; AMBIENT TEMPERATURE; ELECTRON DENSITY; ELECTRON TEMPERATURE; EQUIPMENT; HT-7U TOKAMAK; LIGHT SCATTERING; OPTICAL FILTERS; PHOTODIODES; PHOTONS; PLASMA DIAGNOSTICS; READOUT SYSTEMS; SIGNALS; SIGNAL-TO-NOISE RATIO; TEMPERATURE MEASUREMENT; THOMSON SCATTERING