The Absorption of One-Half Centimeter Electromagnetic Waves in Oxygen

Abstract

The absorption of electromagnetic waves in the one-half cm wave-length range has been measured for ${\mathrm{O}}_{2}$ and ${\mathrm{O}}_{2}$-${\mathrm{N}}_{2}$ mixtures as a function of pressure. The apparatus employs a klystron oscillator, crystal-rectifier frequency-multiplier, wave guide absorption path, and crystal detector. The measured values are in agreement with the theory of Van Vleck both as regards the absolute value of the absorption (which is as great as 67 db/km at the band center for pure ${\mathrm{O}}_{2}$ at a pressure of one atmosphere) and the dependence on pressure.