First Measurement of VUV Spectroscopy Using 1 m Normal Incidence Spectrometer on HL-2A

A 1 m vacuum ultraviolet (VUV) spectrometer with temporal and spatial resolutionwas developed for impurity study of HL-2A tokamak.The instrument is equipped with twoconcave gratings blazed at 80 nm and 150 nm,respectively,and a windowless back-illuminatedcharge coupled device (CCD) detector of 256r×1024 pixels.The total wavelength coverage ofspectrometer is 30～320 nm with a spectral resolution of 0.015 nm at a width of entrance slit of10 μm.A portion of this range is observed during a plasma discharge with a spectral range of20 nm.The minimum integration time of the detector system is about 6.7 ms for each frame in afull binning mode.Using a space-resolved slit located between the entrance slit and the gratinga radial profile on the vertical direction with a range of 400 mm can be obtained.The primaryresults were successfully obtained with high signal-to-noise ratio and good spectral resolution,which demonstrated the instrument functions very well.