Physical properties of Plasma Jets Emitted in Pulsed Capillary Discharges.

Open ends pulsed capillary discharges (PCD) establish natural conditions for the generation of plasma jets. We have investigated the physical properties of the plasma jet emitted in a PCD, operating in a continuous pulsing mode at 10 kV ($\sim $2 kA, 10 ns), with frequencies up to 50 Hz. The discharge is operated in argon and nitrogen, at pressures in the 0.4---1.0 Torr range. A dual, optoisolated, fast Langmuir probe, placed at the anode side, close to the capillary exit, is used to measure the characteristic electron temperature (T$_{e})$ and electron density (N$_{e})$ of the plasma jets, with temporal and spatial resolution. Time integrated visible spectroscopy is used to identify the plasma jets components. Characteristic values of T$_{e}$ and N$_{e}$ are found to be in the tens of eV and 10$^{13}$ cm$^{-3}$, respectively. Based on these measurements, a comprehensive characterization of the PCD plasma jets will be presented.