A five-channel far-infrared (FIR) hydrogen cyanide (HCN) laser interferometer was developed to measure plasma electron density profile on the HT-7 superconducting tokamak. The principle and structure of the five-chann...A five-channel far-infrared (FIR) hydrogen cyanide (HCN) laser interferometer was developed to measure plasma electron density profile on the HT-7 superconducting tokamak. The principle and structure of the five-channel FIR laser interferometer is described. The laser source used in the interferometer was a continuous wave glow discharge HCN laser with a 3.4 m cavity length and a 100 mW power output at 337μm wavelength. The temporal resolution was 0.1 ms and the detection sensitivity was 1/12 fringe. Preliminary experimental results measured by the interferometer on HT-7 tokamak are reported.展开更多
A new multi-channel far infrared (FIR) laser interferometer was built up and ap- plied to HL-2A. The unique feature of real-time heterodyne interferometer is the combination of high power radiation source (300 mW)...A new multi-channel far infrared (FIR) laser interferometer was built up and ap- plied to HL-2A. The unique feature of real-time heterodyne interferometer is the combination of high power radiation source (300 mW), lower noise room temperature detector (noise tempera- ture below 6000 K) with good spatial resolution of 7 cm. Various parameters are optimized for maximum laser output power. Zero crossings of the signals are counted with field programmable gate array (FPGA) digital circuitry yielding the resolution of 1/1000 fringe. The newly measured results including density fluctuation are also presented.展开更多
Structure, improvements and experiment results of a vertical three-channel far- in- frared (FIR) hydrogen cyanide (HCN) laser interferometer, operated routinely in EAST to measure the electron density profile, are...Structure, improvements and experiment results of a vertical three-channel far- in- frared (FIR) hydrogen cyanide (HCN) laser interferometer, operated routinely in EAST to measure the electron density profile, are presented. Moreover, a five-channel deuterium cyanide (DCN) laser interferometer was developed successfully. Some key issues confronted in development, including the economization of working gas and the solution to atmospheric absorption, are resolved and described in detail.展开更多
文摘A five-channel far-infrared (FIR) hydrogen cyanide (HCN) laser interferometer was developed to measure plasma electron density profile on the HT-7 superconducting tokamak. The principle and structure of the five-channel FIR laser interferometer is described. The laser source used in the interferometer was a continuous wave glow discharge HCN laser with a 3.4 m cavity length and a 100 mW power output at 337μm wavelength. The temporal resolution was 0.1 ms and the detection sensitivity was 1/12 fringe. Preliminary experimental results measured by the interferometer on HT-7 tokamak are reported.
基金National Natural Science Foundation of China (Nos.10575030,10675043)the JSPS-CAS Core University Program in the field of Plasma and Nuclear Fusion
文摘A new multi-channel far infrared (FIR) laser interferometer was built up and ap- plied to HL-2A. The unique feature of real-time heterodyne interferometer is the combination of high power radiation source (300 mW), lower noise room temperature detector (noise tempera- ture below 6000 K) with good spatial resolution of 7 cm. Various parameters are optimized for maximum laser output power. Zero crossings of the signals are counted with field programmable gate array (FPGA) digital circuitry yielding the resolution of 1/1000 fringe. The newly measured results including density fluctuation are also presented.
文摘Structure, improvements and experiment results of a vertical three-channel far- in- frared (FIR) hydrogen cyanide (HCN) laser interferometer, operated routinely in EAST to measure the electron density profile, are presented. Moreover, a five-channel deuterium cyanide (DCN) laser interferometer was developed successfully. Some key issues confronted in development, including the economization of working gas and the solution to atmospheric absorption, are resolved and described in detail.