Sonoluminescence produced by ‘‘stable’’ cavitation

This article reports on a phenomenological study of sonoluminescence produced by acoustic cavitation in which a sensitive, high-gain image intensifier tube (EMI type 9912) was used to view the cavitation. We discovered that large amounts of light were being emitted from regions near pressure antinodes in the standing wave field where the pressure amplitude was approximately 0.17±0.03 MPa. Visual observation of these areas indicated activity resembling ‘‘stable’’ cavitation rather than ‘‘transient’’ cavitation.