SONOLUMINESCENCE FROM AN ISOLATED BUBBLE ON A SOLID-SURFACE

Measurements of sonoluminescence from isolated cavities that spontaneo usly form on solid objects in a fluid-filled acoustic resonator are re ported. The subnanosecond light flashes have a smooth ultraviolet spec trum similar to that from single bubbles, although with organic liquid s low intensity Swan lines ride on the continuum. The hemispherical ca vities reach maximum radii about five times larger than are realized i n sonoluminescence from single bubbles. The sonoluminescence-intensity continues to increase as the liquids are cooled to temperatures as lo w as 160 K.