Abstract
In experiments of sonoluminescence (SL) at 1MHz, we found extraordinary light emission. The extraordinary light was observed only when we used transducer which was partly removed by cavitation erosion. To clarify the origin of the extraordinary light of SL, we have measured SL distribution and spectrum. With damaged transducer, SL intensity is much larger than that of normal SL. Also continuum components from SL increased and conformed to helium emission lines. We also measured AC voltage leaked from the damaged transducer surface and obtained A high value at near the part was removed.
