2aPA11. Mass flux resonance and the threshold for light emission in single bubble sonoluminescence.

Session: Tuesday Morning, June 17

Author: R. Glynn Holt
Location: Dept. of Aerosp. and Mech. Eng., Boston Univ., 110 Cummington St., Boston, MA 02115
Author: D. Felipe Gaitan
Location: Univ. of Mississippi, University, MS 38677


The acoustic pressure, equilibrium, and time-varying radius of single air bubbles acoustically levitated in a 20-kHz acoustic standing wave have been measured in the region of parameter space where light emission from bubbles is observed. A resonancelike response of the bubble oscillation is observed along the path in parameter space to which the bubble equilibrium radius is constrained by an unknown mass flux mechanism. A partial explanation of the anomalous stability observed previously [R. G. Holt and D. F. Gaitan, Phys. Rev. Lett. 77, 3791 (1996)] is presented. The bubble response is correlated with the threshold for light emission and light intensity as a function of increasing acoustic pressure. Finally, the measured bubble response is shown to agree with the Rayleigh--Plesset equation, even though the theory cannot predict the equilibrium path in parameter space. [Work supported by NASA.]

ASA 133rd meeting - Penn State, June 1997