Dynamics of a Pulsed Plasma Gas discharge

The linear Z pinch discharge occurred in a cylinderical Pyrex glass vessel of 11.0 cm diameter and 25.0 cm long, between the two end aluminum electrodes. The vessel is evacuated using the a rotary pump to a base pressure of 20 mTorr, the working gas is argon and is introduced by aneedle valve to a pressure of 10 mTorr. The electric circuit is composed offour capacitors of 7. 71 ~F, 1.25 kJ each. They are arranged in a parallelcombination to give a total capacitance of30.84 ~F. We use a power supply of45 kV to charge the capacitor bank, the discharge occurs through a pressurizedspark gap externally triggered by a high voltage trigger signal of 14 kV. Theplasma is stablized, by an an external return current of six copper cablesdistributed along the discharge vessel and are fed with the discharge current.The total discharge current is 28.5 KA with a periodic time of 28 us. Theelectrical parameters of the system is, 91 m n total system resistance and 644oH total system inductance.Many diagnostic techniques are used such as; Rogowski coil, capacitivecoupling potential divider, magnetic probe and spectroscopy by using relativecontinuum intensity radiation method. A special design of capacitive couplingpotential divider is used which consists of two parallel thin plates with area 41cm2 and are separated by an insulating sheet ofpolysteren of thickness 2mm and it forms a capacitor of 46 pF. One plate is connected to the high voltage electrode, and the other is connected the 160 nF capacitor with shunt resistor 500 n and the output is taken on it. The spectroscopic diagnostic is mainly a photomultiplier which collects light through a colored filter, for perturbation reason the light from the discharge is fed to the photomultiplier through a lightguide .. The electron temperature is calculated from the measurements of theintensity of continuum radiation at two different wavelengths A1 and A2 .