A potential experiment for in-situ measurement of atmospheric temperature and atomic oxygen density in the 90-150Â km altitude range by a Raman Lidar

The Raman backscatter cross sections for a 355 nm light source for the three fine-structure components are calculated. The signal-to-noise considerations show that the determination of the densities of the three fine-structure components separately is a feasible experiment. Since these fine-structure components are calculated to be in local thermodynamic equilibrium up to at least 350 km altitude, this experiment also gives atmospheric temperature. It is pointed out that this experiment does not suffer from the drawbacks of the previous efforts to determine atomic oxygen density and should yield reliable results for this density as well as temperature.