A Scanning SXR Spectrometer Used in Experiments on ECR Plasma Heating at the L-2M Stellarator

Abstract

Abstract—A diagnostic complex that is based on a scanning soft X-ray spectrometer has been developed at the Prokhorov General Physics Institute. The diagnostic complex is intended to measure the radial profiles of the plasma electron temperature in the L-2M stellarator. The maximum counting rate of the spectrometer is 2.0 × 10⁵ pulses/s. It allows measuring of SXR spectra in the energy range of γ-photons of 1–80 keV. The spectral resolution of the spectrometer measured using a source of radioactive radiation with energy of E = 5.89 keV (⁵⁵Fe) was ΔE = 320 eV (FWHM). The scanning system makes it possible to measure SXR spectra along the chords lying in the angular range from –13.5° to +26.5°. Negative and positive angles correspond to chords below and above the equatorial plane of the facility, respectively. The radial resolution of the spectrometer at the plasma axis is ~1.7 cm. The first results of spectral measurements in experiments at electron cyclotron resonance plasma heating at the L-2M stellarator are presented.