Evidence of Soft X-Ray Lasing in SIGNAL Pulsed-Power Facility Experiments With Argon Capillary Plasma

This paper presents the results of temporal measurements of the soft X-ray radiation intensity in the spectral range of 10-40 eV emitted from the capillary plasma under discharge with a current pulse of 26 kA amplitude and rising rate of about 10¹² A/s. The experiments were carried out on a pulsed-power facility SIGNAL with ceramic capillaries of 0.3 cm inner diameter and 15.7 cm length, which are filled with argon up to pressures in the range of 0.25-0.5 torr. To interpret the experimental results, a sequence of numerical calculations simulating gas dynamics and level-by-level ionic kinetics of argon plasma was used. The effect of X-ray lasing in the Ne-like line was found to be generated with a quanta energy of 26.4 eV, which lasted for approximately 1-2 ns, at a moment of about 33 ns after the current pulse start