Large volume penning plasma discharge source: An efficient light emitting source for the visible and VUV radiations simultaneously

In the applications of light emitting sources it has recently been proposed that a penning plasma discharge device can be used to calibrate a VUV spectrometer-detector system which will be an easy and low cost method in comparison to the commonly known branching ratio method used in Tokamak plasmas. In this paper a large volume penning discharge source as an efficient light emitting source for both the visible and VUV radiation simultaneously is reported. Two different anode geometries have been developed for light efficiency analysis, which includes rectangular anode and double anode rings. The experiments have been performed for different working pressures, admixture of gases and discharge voltages. The developed source is able to produce large number of spectral lines in the shorter wavelengths of VUV range from the buffer gases and not by electrode materials as compared to other sources. The images of the ICCD camera are used to understand the emission pattern, and the diffusion of plasma for different exposure times with different experimental conditions, each of which exhibiting an unlike spatial emission pattern. The emission pattern of double ring shows bright discharge region at the center as compared to the rectangular configuration. Simulations have also been carried out using OMNI Track and VORPAL particle-in-cell simulation codes to perceive the particle trajectories from the electric field profile and potential distribution of the developed configurations. The intensity variation of the observed spectral lines shows that the visible and VUV spectral line intensities are more sensitive at higher working pressures and gives higher emission in double ring configuration. The present study suggest that the double ring configuration penning plasma discharge source is a better source for VUV-spectrometer detector system calibration application.