title: Compact focusing spectrometer: visible (1 eV) to hard x-rays (200 keV).
abstract: A low-cost spectrometer that covers a wide range of photon energies can be useful to teach spectroscopy, and for simple, rapid measurements of the photon spectrum produced by small plasma devices. The spectrometer here achieves its wide range, nominally from 1 eV to 200 keV, with a series of spherically and cylindrically bent gratings or crystals that all have the same shape and the same radius of curvature; they are complemented by matching apertures and diagnostics on the Rowland circle that serves as the circular part of the spectrometer's vacuum vessel. Spectral lines are easily identified with software that finds their positions from the dispersion of each diffractive element and the known energies of the lines.
authors.affiliation: RNC "Kurchatov Institute", 123098 Moscow, Russia.
authors.forename: E O
authors.initials: EO
authors.lastname: Baronova
authors.affiliation: RNC "Kurchatov Institute", 123098 Moscow, Russia.
authors.forename: A M
authors.initials: AM
authors.lastname: Stepanenko
authors.affiliation: Ecopulse, Inc., 7844 Vervain Ct, Springfield, Virginia 22152, USA.
authors.forename: N R
authors.initials: NR
authors.lastname: Pereira