Douglas J. Durian, University of Pennsylvania, Philadelphia, PA and Alex S. Gittings, UCLA, Los Angeles, CA.
Speckle-Visibility Spectroscopy is a dynamic light scattering technique capable of resolving fluctuating or unsteady dynamics. Here we use it to study in detail the nature of bubble rearrangements in a coarsening foam. In particular we measure the statistical distribution of event durations, speeds, and time between events. By constrast, usual methods yield only the average time between events.