A spectral line survey from 17.5–250 nm of plasmas created in a magnetic confinement device

Abstract

Abstract Spectral emission lines continue to be a powerful tool for studying astrophysical, process, laser-produced, and magnetically confined plasmas, among others. Hence, numerous spectroscopy-based plasma diagnostics, from the x-ray to the infrared, make use of the relative intensity, width, displacement in wavelength, or temporal evolution of such emission lines emitted by the atoms and ions present in such plasmas. In this work, a spectral line survey, from 17.5–250 nm, is presented for electron cyclotron resonance heated (ECRH) and neutral beam injection (NBI) heated plasmas created and maintained in the TJ-II stellarator, a medium-sized magnetically confined plasma device. In these plasmas, for which hydrogen, deuterium or helium have been used as the working gas, central electron temperatures and densities up to 1 keV and 5 × 1019 m−3, respectively, are achieved. This work is a compilation of the identified spectral emission lines emitted by the working gas as well by the intrinsic and injected impurity ions in the above wavelength range. For this, spectra were recorded, over the past fifteen years of TJ-II operation, using a 1 m focal length normal incidence spectrometer equipped with a charge-coupled detector at its output focal plane. In total, almost 400 spectral emission lines from eighteen different elements have been identified using a number of atomic line emission databases.