Water vapor absorption of carbon dioxide laser radiation.

An optoacoustic detector or spectrophone has been used to perform detailed measurements of the absorptivity of mixtures of water vapor in air. A C(12) O(2)(16) laser was used as the source, and measurements were made. at forty-nine different wavelengths from 9.2 microm to 10.7 microm. The details of the optoacoustic detector and its calibration are presented, along with a discussion of its performance characteristics. The results of the measurements of water vapor absorption show that the continuum absorption in the wavelength range covered is 5-10% lower than previous measurements.