Spectroscopic Characterization of Electron Beam Induced Plasma in Different Gases

The plasma chemistry generated by an electron beam emitted from a Febetron pulsed-power generator operating in different background gases is being investigated spectroscopically. The generator located at the Naval Research Laboratory produces a peak voltage of 80 kV, peak current of 4 kA with a pulse width of 100 ns. Once formed, the electron beam passes through a thin anode followed by a thin pressure barrier into a volume filled with different background gases at pressures ranging from 1000 to 10 mtorr. The volume is filled with both molecular (nitrogen and air) and atomic gases (Ar) to study the behavior of the generated plasma in these different conditions. The present work focuses on analysis of the emission spectrum from the electron beam generated plasma; of particular interest are spectral lines from the near ultraviolet to the visible (300 nm to 600 nm). The temporal and spatial variation of excited species are studied to understand the characteristics of the plasma.