Interaction of a converging shock wave with a plasma

(Experimental studies of a spherical converging shock wave (SW) interaction with preliminary formed plasma are presented. The SW was generated by an underwater electrical explosion of a spherical Cu wire array (radius of 15 mm, number of wires of 40, and wire diameter of 0.1 mm) supplied by 240 kA amplitude current pulse with rise time of ∼0.8 μs. The plasma was formed by a 40 Pa propane discharge between the cathode and anode electrodes, placed at the distance of 1.5 mm apart, inside of 2 mm inner diameter quartz capillary located at the equatorial plane of the array. The light emission from the plasma was transferred to the inputs of two spectrometers by optical fiber installed from the one side of the capillary and beam splitter with lenses. The spectral lines intensities at the output of spectrometers were recorded prior and during the SW interaction with plasma by intensified framing 4QuikE cameras and by a photomultiplier tube when one of the spectrometers was used as a monochromator.