NASA ER-2 Lyman Alpha Hygrometer Data

The instrument used the techniques of photofragment fluorescence combined with dual path absorption to measure water vapor concentrations ranging from 1013 to 1016 molecules/cubic centimeters at pressures from 50 to 500 mb. The detection scheme utilized the Lyman-Alpha photons (121.6 nanometers) to photo- dissociate water vapor and produce excited OH molecules which emit photons that are detected by a photomultiplier near 314 nanometers.

Units are in ppmv. Principal Investigators were Weinstock, Dessler, Hintsa, and Anderson (Harvard University).