A new mechanism for sonoluminescence

It is argued that a pulsating acoustically levitated bubble cannot possibly maintain a spherical shape. A jet forms during compression, and the sound amplitude such that the jet first strikes the other side of the bubble with sufficient energy is hypothesized to be the threshold for sonoluminescence. It is proposed that the connection between jet impact and light emission is a fracturing of the liquid that cannot flow during the extremely short time scale over which pressure is applied. With this hypothesis, sonoluminescence would therefore be a manifestation of the non-Newtonian nature of water and other simple liquids when stressed with sufficient intensity and rapidity. (C) 1997 Acoustical Society of America.