PRESSURE-DEPENDENCE OF THE WATER-VAPOR CONTINUUM ABSORPTION IN THE 3.5-MU-REGION 4.0-MU-REGION

A line tunable deuterium fluoride laser was used to measure the pressure dependence of the water vapor continuum absorption at 25°C in the 3.5–4.0-μm spectral region.From measurements of the absorption of 14.3 Torr of deuterium depleted water vapor buffered by several air-broadening pressures, an unexpectedly small foreign-to-self-broadening coefficient of 0.011 with a factor of 2 uncertainty as well as an unusually strong self-contribution for the water vapor continuum absorption were observed.These measurements can be used to infer contributions to the water vapor continuum in the 3–5-μm window from both far wing and aggregate-water-molecule type absorptions.© 1979 Optical Society of America.