The cavitation collapse on a sub-ns time scale

A single sonoluminescing air bubble trapped in the pressure maximum of a resonant sound field in water is an ideal model system to investigate the end phase of the cavitation collapse. The dynamics of these single bubbles can be characterized with Mie‐scattering. In earlier experiments, the scattered light was detected with photomultiplier tubes (PMT) where the time resolution is limited by the response of the PMT and no spatial resolution is possible. Using a streak camera, the scattered light can be recorded with high spatial and temporal resolution. The streak images show that at the minimum radius the scattered light intensity is not only a function of R(t) anymore, and the changes in the refractive indices inside the bubble and in the highly compressed water surrounding the bubble have to be considered. Together with the width and intensity of the emitted light pulses, the results represent a complete data set for the end phase of the bubble collapse.