Title :
Spot Mode Operation of a Low-Pressure Helium–Xenon Glow Discharge
Author :
Winter, Jörn ; Lange, Hartmut
Author_Institution :
Leibniz Inst. for Plasma Sci. & Technol., Greifswald, Germany
Abstract :
The cathode region (CR) of a low-pressure He-Xe discharge with a flat thermionic emitting cathode in spot mode has been experimentally investigated by means of tunable diode laser absorption spectroscopy. Due to the strong inhomogeneity of the spot plasma, a multidimensional consideration of the CR is necessary to obtain correct results. This was achieved by an experimental setup, which provides a space-resolved measurement of the absorption signal. Furthermore, the plasma inhomogeneity was considered in the subsequent analysis of the obtained data too. The gas temperature in the surrounding volume was determined. Furthermore, the spatial density profile of the xenon 6s[3/2]2 metastable atoms was measured in the vicinity of the spot.
Keywords :
glow discharges; helium; plasma density; plasma diagnostics; plasma light propagation; plasma temperature; thermionic cathodes; xenon; He-Xe; absorption signal; cathode region; flat thermionic emitting cathode; gas temperature; low pressure helium-xenon glow discharge; metastable atoms; plasma inhomogeneity; space resolved measurement; spatial density profile; spot mode operation; tunable diode laser absorption spectroscopy; Atomic measurements; Cathodes; Discharges; Plasma temperature; Temperature measurement; Xenon; Atom number density; LAAS; gas temperature; helium; mercury-free low pressure discharge lamp; spot mode; xenon;
Journal_Title :
Plasma Science, IEEE Transactions on
DOI :
10.1109/TPS.2011.2150245
