Temperature measurements by ultraviolet filtered Rayleigh scattering using a mercury filter uri icon

abstract

  • We report the development of Ultraviolet Filtered Rayleigh Scattering (UV FRS) as a diagnostic tool for measurements of gas properties. A frequency tripled, narrow linewidth, Ti:sapphire laser illuminates a sample, and Rayleigh scattered light is imaged through a mercury vapor absorption filter. The strong absorption of the filter may be used to suppress elastic background. Tuning the laser through the absorption notch of the filter is a means of probing the scattering line shape, which contains temperature information. Temperature measurements of air are shown to have uncertainties of less than 3%, whereas measurements of a weakly ionized discharge have uncertainties of less than 4%. An enhanced scattering cross section as well as nearly ideal filter properties lead to temperature sensitivities for the mercury filter in the ultraviolet which are comparable to those available with an iodine filter in the visible. The absorption for the mercury filter is modeled to be at least 5 orders of magnitude higher than for the iodine filter, meaning that stronger background suppression may be achieved.

author list (cited authors)

  • Yalin, A. P., & Miles, R. B.

citation count

  • 19