In this Letter we describe measurements of the light emission evolution for single-bubble sonoluminescence. In particular, we show that the evolution of intensity for an air bubble depends on whether or not the bubble has previously been in a steady sonoluminescence state. Our results provide strong experimental evidence in support of the recent hypothesis that an air bubble undergoing single-bubble sonoluminescence in water transitions to an argon bubble.

• Received 6 August 1997

DOI:https://doi.org/10.1103/PhysRevLett.80.865