Generation of Soft X-Ray and Vacuum Ultraviolet Radiation during the Interaction of a Hydrogen Plasma Flow with a Gas Jet

Abstract

Results are presented of research aimed at creating a compact source of soft X-ray and vacuum ultraviolet radiation through the collision of a powerful plasma flow with a gas jet. In experiments that were carried out, a pulsed electrodynamic accelerator generated a hydrogen plasma flow with an energy constant of ≈50 kJ and duration of 10–15 μs. The flow, with a density of ≈6 × 10¹⁵ cm^–3, moved at a velocity of (2‒4) × 10⁷ cm/s in a longitudinal magnetic field with an induction of up to 2 T and interacted with a flat supersonic gas jet. The maximum molecular density of the gas, nitrogen or neon, in the jet reached 10¹⁷ cm^–3. The formation of a compact emitting plasma layer with a thickness of 3–5 cm, moving along the path of the hydrogen plasma flow at a speed of approximately 3 × 10⁶ cm/s was demonstrated. In several experiments, a tungsten plate was used as an obstacle to confine the motion of the emitting plasma along the magnetic field, localizing the interaction region between the plasma flow and the gas jet within the diagnostic control zone. Soft X-ray obscurography and spectroscopy were used to obtain data regarding the radiation generation from the interaction zone of the hydrogen plasma flow and the gas jet. The results of measuring the radiation energy from the formed plasma are presented: ≈2 kJ in the case of a nitrogen jet and ≈ 3 kJ in the case of a neon jet. Numerical modeling of the line radiation from multi-charged ions and subsequent comparison of calculated and experimental data allowed estimating the electron temperature of the nitrogen and neon plasmas formed during the interaction of the hydrogen plasma flow with the gas jet at a level of ≥40 eV.