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Updated: Jun 15, 2026

10:21
Evanescent Field Based Photoacoustics: Optical Property Evaluation at Surfaces
Published on: July 26, 2016
Abstract:
Some types of photoacoustic spectroscopy sample cells exhibit acoustic resonances which are not explained by organ pipe or Bessel mode analysis. It is demonstrated here that one type of acoustic resonance encountered is explained by a Helmholtz resonator analysis. Its properties are studied as a function of the dimensions of the channel connecting the sample chamber and the microphone housing chamber.
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