Multi-Channel Scanning Filter Spectrometer for the Beam Emission Spectroscopy

Abstract

Multi-channel scanning filter spectrometer with narrow band pass of 2 nm is installed in Large Helical Device (LHD) for Beam Emission Spectroscopy (BES) using hydrogen (H) and deuterium beam (D). The spectral shape of transmitted light (half width at half maximum, skewness and kurtosis) is measured using the monitor grating spectrometer coupled with the filter spectrometer. No distortion of the spectrum shape is observed in the wavelength scan range of 8 nm required for the Doppler shift of the BES emission from H-beam and D-beam.