Frequency dependence of a quartz oscillator on gas pressure

TLDR: In this paper, the frequency shifts of a tuning fork-shaped quartz oscillator with gas pressure were studied experimentally and theoretically and the experimental measurements showed that the frequency shift of the oscillator was very small in the pressure region below 1 Torr and much larger in the higher pressure region above 1 torr.

Abstract: The frequency shifts of a tuning‐fork‐shaped quartz oscillator with gas pressure were studied experimentally and theoretically. The experimental measurements showed that the frequency shift of the oscillator was very small in the pressure region below 1 Torr and much larger in the higher pressure region above 1 Torr. The experimental results were theoretically analyzed on the basis of a string‐of‐beads model for a quartz oscillator. The theoretical analysis showed that the resonance frequency shift of the quartz oscillator was small in the molecular flow region. In the viscous flow region the frequency shift was found to be proportional to the pressure. These theoretical results are in good agreement with the experimental data. The frequency shift of the oscillator in the higher pressure region was also found to be proportional to the molecular weight of the gas species in both theory and experiment.