Time-resolved spectroscopic measurement of anode plasma in magnetically-insulated diode

Abstract

A new diagnostic technique has been developed for the time-resolved spectroscopic measurement of anode plasma in a single-current-feed magnetically-insulated iondiode. From the measurement of Stark broadening of Hα line of hydrogen, we have estimated the electron density to be 4 ∼ 5 × 1016 cm−3 using the pulse-power generator, ‘ETIGO-I’, typically operated with diode voltage, 550 and 600 kV, diode current, 36 and 53 kA, and pulse width ∼ 90 ns (FWHM of diode current). Assuming local thermodynamic equilibrium, we have estimated the electron temperature to be l·9∼2·4eV from the measurement of light intensity ratio of successive ionization stages of carbon. The expansion velocity of the anode plasma has been found to be 4∼4·5cm/μS.