High-Etendue High-Resolution Spectrometer−Polychromator Equipped with Novel sCMOS Cameras for Tokamak Plasma Spectroscopy.

An improved prototype of the large-aperture, high-resolution spectrometer−polychromator (the so-called high-etendue spectrometer, HES) has been designed for spectroscopy diagnostics of plasma, in particular, for the Charge-eXchange Recombination Spectroscopy (CXRS) diagnostics at the ITER facility. Ion temperature profiles, poloidal and toroidal plasma rotation velocities, and low-Z impurity densities can be measured using the CXRS technique. The HES is equipped with novel, high-efficiency compact sCMOS cameras with low noise level, wide dynamic range, high quantum efficiency, and almost 100% working cycle. The HES is based on three transmission holographic gratings, which allow its simultaneous operation in three spectral bands: 468 ± 5, 529 ± 5, and 656 ± 6 nm. The main performance characteristics of the cameras, transmission gratings, and the spectrometer as a unit have been measured. It has been established that the characteristics of the developed HES satisfy the requirements for the spectroscopic equipment intended for measurements of the ITER CXRS diagnostic system. [ABSTRACT FROM AUTHOR]