Abstract
An experimental investigation into the origin of satellite resonances has been carried out by the author. They are identified as mode resonances of the gas in the interferometer tube and are of the type described by Lord Rayleigh. The presence of unresolved satellites in the principal interferometer resonance introduces a considerable error into absorption measurements. Results obtained by Van Itterbeek and his co-workers are shown to be in agreement with the Krasnooshkin interferometer theory, which takes into account the effect of the multiple nature of the principal resonance. A criterion for the choice of crystals for ultrasonic absorption measurements is given.