Abstract
Intensity of sonoluminescence(SL) in water or sonochemiluminescence(SCL) in luminol solution has been known to exhibit a maximum when it is measured as ultrasonic power increases. We measured SL and SCL intensity using free-end cell and fixed-end cell. The results showed intensity maxima in both cases. We observed that the decrease in the intensity was caused by a perturbation of liquid surface in the case of the free end, and by a violent cavitation event accompaning hissing noise in the case of the fixed end. Measurement of acoustic emission in the case of the fixed end showed the increase in continuous spectrum when SL was quenched.
