Loss mechanisms in resonant spectrophones

Quality factors and resonant frequencies of a resonant spectrophone have been measured as a function of pressure and the results compared to theoretical predictions which took into account classical surface and volumetric losses and molecular relaxation. Buffer gases investigated included the five noble gases, H(2), N(2), O(2), CO(2), N(2)O, and SF(6). Typically 95% of the cavity losses were accounted for theoretically. Frequency shifts due to relaxational dispersion, nonideal gas behavior, and classical boundary layer effects were observed; all behaved as predicted by theory.