We have repeated the experiment of Taleyarkhan et al. [Science 295, 1868 (2002)] in an attempt to detect the emission of neutrons from $d\mathrm{\text{−}}d$ fusion during bubble collapse in deuterated acetone. Using the same cavitation apparatus, a more sophisticated data acquisition system, and a larger scintillator detector, we find no evidence for 2.5-MeV neutron emission correlated with sonoluminescence form collapsing bubbles. Any neutron emission that might occur is at least 4 orders of magnitude too small to explain the tritium production reported in Taleyarkhan et al. as being due to $d\mathrm{\text{−}}d$ fusion. We show that proper allowance for random coincidence rates in such experiments requires the simultaneous measurement of the count rates in the individual detectors.

• Received 17 July 2002

DOI:https://doi.org/10.1103/PhysRevLett.89.104302