Precision measurements of the wavelengths of spectral lines of multiply charged krypton and argon ions formed in a gas target heated by laser radiation

The first precision (with an error of 0.4 — 1.6 mÅ) measurements were made of the wavelengths of x-ray spectral lines emitted as a result of n = 4 — n' = 2 transitions in the Ne- and Na-like Kr XXVII and Kr XXVI ions. The spectra were recorded by means of a spectrograph with a spherically bent mica crystal, characterised by a spectral resolution λ/Δλ ≈ 5 × 10³. The dispersion characteristic of this crystal was determined with the aid of reference lines, which were emitted by the He-like Ar XVII ion. The wavelengths of a series of dielectronic satellites of the resonance line of the Ar XVII ion were identified and measured. The results obtained were compared with calculated data.