Temporally resolved electron density of a repetitive, nanosecond pulsed microdischarge

Using high speed spectroscopic diagnostics, temporally resolved optical emission spectroscopy is performed on a nanosecond, repetitively pulsed microdischarge. The microdischarge operates in an argon–hydrogen gas mixture (99%/1%) to provide a Lyman-α vacuum ultraviolet emission. Based on the Stark broadening of the 486.1 nm, Balmer-β hydrogen transition, the temporally resolved electron density was determined. Experimental electron density data are compared with the results of a 0D rate equation model. Peak electron density is estimated to be 5.6 · 10¹⁵cm⁻³, corresponding to a ∼0.25% degree of ionization. Using the approximate experimental ionization rate, the electron temperature is estimated to be ∼3.5 eV. (paper)