OBSERVATION OF STABILITY BOUNDARIES IN THE PARAMETER SPACE OF SINGLE BUBBLE SONOLUMINESCENCE

The region of parameter space (acoustic pressure P-a, bubble radius R( 0)) in which stable single bubble sonoluminescence (SBSL) occurs in an air-water system is a small fraction of that which is accessible. Thi s is due to the existence of an island of dissolution at high P-a and small R(0). For dissolved gas concentrations above 50% of saturation, the region lies above the threshold for shape oscillations and is unob servable. Below 50%, an oscillating bubble is stabilized on the bounda ry of the island which lies below the shape threshold. SBSL is shown t o exist exclusively along this boundary.