Absorption of radiation by water vapor in windows of relative transparency of 95-145 micrometer range

The results of spectrometric measurements and theoretical calculations of the absorption coefficients for pure and atmospheric water vapor in six submillimeter windows of relative transparency are compared. It is found that in all the windows the measured absorption exceeded the theoretically calculated values by about 1.14. For pure water vapor the divergence was even larger. The divergence is compared with data from a number of other studies and is found to be in agreement. Some recommendations are offered for reducing the discrepancy in order to obtain more accurate data.