Development of a nanosecond discharge-enhanced laser plasma spectroscopy

A nanosecond pulse discharge circuit is developed and used to enhance the optical emission of laser plasma. An intense discharge spark was observed with a peak discharge current of 1.9 kA and a peak power of 6.5 MW. The main electric energy deposition only lasted for ～40 ns. An intense optical emission was observed. The line intensity of plasma emission was greatly increased along with an improved signal-to-noise ratio, in comparison with that using a microsecond pulse discharge circuit. From the measured spectra, electron temperature and electron number density were estimated. The mechanism of the optical emission enhancement was briefly discussed.