SONOLUMINESCING AIR BUBBLES RECTIFY ARGON

The dynamics of single bubble sonoluminescence (SBSL) strongly depends on the percentage of inert gas within the bubble. We propose a theory for this dependence, based on a combination of principles from sonoch emistry and hydrodynamic stability. The nitrogen and oxygen dissociati on and subsequent reaction to water soluble gases implies that strongl y forced air bubbles eventually consist of pure argon. Thus it is the partial argon (or any other inert gas) pressure which is relevant for stability. The theory provides quantitative explanations for many aspe cts of SBSL.