HIGH INTENSITY LASER PROPAGATION IN THE ATMOSPHERE. IV. FAR WING PRESSURE BROADENING.
Abstract
The residual absorption in the 10 micrometers window is considered to be due in large measure to the very far wings of the pure-rotational lines of H2O. Experimental data indicate the broadening is mainly self-broadening arising from binary collision between H2O molecules. In order to explain the relatively large absorption observed at 10 micrometers, studies were carried out based upon a model of hindered rotational motion (libration) in which the ordinary rotational motion is suppressed by the strong dipole-dipole force during close collisions. Present results give a cross section which is one-half the experimental value multiplied by a Boltzmann factor describing the probability of achieving a frequency-matching configuration. It was found that for the particular model studied that this factor is too small. However, our studies indicate a variety of possible modifications which are capable of obtaining agreement with experiment. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1968
- Accession Number
- AD0678422
Entities
People
- Theodore D. Holstein