Interferometric Measurements of Anomalous Dispersion in Hydrogen Fluoride.
Abstract
Quantitative measurements of unsaturated anomalous dispersion of the P sub 1 (4) and P sub 1 (6) vibration-rotation transitions of hydrogen fluoride (HF) in absorption are reported. Contained also are measurements of the partially-saturated P sub 1 (4) transition. All measurements were obtained with an interferometric approach at pressures less than ten torr. A Fabry-Perot interferometer was used to spatially resolve the axial modes of an HF probe laser. A Michelson interferometer, one leg of which contained an HF absorption cell, imposed lines of constant phase. Fringe shifts were recorded and used to determine the refractive index change between axial mode frequencies. The unsaturated results compare favorably with computer-generated theoretical curves which account for proper amounts of pressure and Doppler broadening. A simple rate-equation model for the saturated results is proposed as an initial step in understanding the complex pressure-dependent relaxation processes occuring in this particular gas. The experimental results indicate a combined state-altering and velocity-changing collision rate of 11,000,000/sec-torr, a value lying between the total line-broadening rate and the gas kinetic (hard sphere) rate.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1985
- Accession Number
- ADA156937
Entities
People
- J. M. Rabins
Organizations
- Air Force Institute of Technology