Yuri T. Didenko and Kenneth S. Suslick of the University of Illinois at Urbana - Champaign studied single bubbles in water subjected to ultrasound and, for the first time, established an energy inventory for the collapsing spheres. (scientificamerican.com)
But Williams's group proved that isn't the case, creating larger - than - usual single bubbles whose spectra included the missing emission. (scientificamerican.com)
Although they don't know why, the researchers say that bubble size alone seems to predict the OH line and suggest that, compared with smaller single bubbles that collapse symmetrically (top right), larger bubbles in multibubble systems are unstable (bottom right). (scientificamerican.com)