Time and space resolved VUV-spectroscopy of a pulsed hollow cathode capillary discharge

We present time and space resolved spectroscopic observations of a pulsed hollow cathode capillary discharge operating in Argon. The discharge is characterized by a fast ∼10 ns, kA level current pulse. A 600 lines/mm grating coupled to a 2.5 ns gated macro channel plate intensifier is used for spectroscopic measurements. A new technique is used to investigate the radial distribution of ionization species. A thin wire across the entrance slit of the spectrometer casts a shadow over the emission lines. The characteristic size of the emitting plasma is inferred from the wire shadow. Highly ionized species, including Ar VII to Ar XI and Al V, are found to be localized on-axis, meanwhile lower ionization stages, Ar VI to Al III and Al IV, fill up to a larger radial extent of the capillary volume