Sonoluminescence stability for gas saturations down to 0.01 Torr

Abstract

Water solutions with very small argon partial pressures were investigated. The experiments were performed in a sealed cell. The argon was used in both a pure form and in mixtures with other gases. A regime of stable sonoluminescence was seen at lower driving pressures for argon partial pressures down to 0.01 Torr. Mie scattering, light pulse measurements, and visual observations over tens of thousands of cycles were used to determine if the bubble was stable. As the drive pressure was increased, the bubble moved into a slow time scale instability on the order of several seconds which sometimes caused break up. These experiments are discussed and compared to other published data involving gas mixtures at saturation levels up to 1 atm.