A new high sensitivity far-infrared laser interferometer for the HL-2A tokamak

作者：Li Y G; Zhou Y; Li Y^*; Deng Z C; Wang H X; Yi J

来源：Review of Scientific Instruments, 2017, 88(8): 083508.

DOI：10.1063/1.4997070

A new four-chord Michelson-type formic acid (HCOOH, lambda = 432.5 mu m) laser interferometer has been successfully commissioned on the HL-2A tokamak to measure the electron density and density fluctuations. Due to the employment of the two-laser heterodyne technique, the time resolution of the interferometer reached 1.0 microseconds (mu s). Four chords of line electron densities with a line-averaged density resolution 2 x 10(16)/m(3) were obtained in a recent HL-2A experimental campaign, and detailed electron density fluctuations, caused by events such as edge localized mode, sawtooth precursor-oscillations, and energetic particle driven instabilities, were distinctly measured. In particular, the high-frequency electron density fluctuations (up to 500 kHz) caused by the reversed shear Alfv enic eigenmode were observed by the internal two interferometry channels, and their fluctuation location could be approximately identified from the spectra characteristics of multi-chord line electron densities. Published by AIP Publishing.

• 出版日期2017-8
• 单位核工业西南物理研究院