OPTICAL PULSE-WIDTH MEASUREMENTS OF SONOLUMINESCENCE IN CAVITATION-BUBBLE FIELDS

Optical pulse width measurements of sonoluminescence from cavitation-b ubble fields have been obtained for two well-defined cavitation zones in an aqueous solution of Glycerin using a fast (650 ps rise-time) PMT and a fast (10 GS/S) digitizer. One zone corresponds to cavitation pr oduced from an ultrasonic homogenizer. A lens was used to focus on a p articular region of ''streaming'' sonoluminescence. A second, more loc alized cavitation zone was produced using a 2-in-diam PZT driving crys tal in a rectangular fluid-filled container. Single-bubble sonolumines cence was used to characterize the response of the PMT to low-level li ght input. The measured rise-time and pulse width for sonoluminescence from cavitation fields is indicative of the response of the PMT and s uggests that the pulse width of cavitation-field sonoluminescence is m uch less than 1.1 ns. (C) 1997 Acoustical Society of America.