Nuclear fusion in collapsing bubbles—Is it there? An attempt to repeat an experiment that reported d–d fusion in bubble collapse induced by cavitation in deuterated acetone

Abstract

The experiment of Taleyarkhan et al. [Science 295, 1686 (2002)] has been repeated [D. Shapira and M. Saltmarsh, Phys. Rev. Lett. 89, 104302 (2002)] in an attempt to detect the emission of neutrons from d–d fusion during bubble collapse in deuterated acetone. Using the same apparatus and method for bubble seeding and cavitation but a more sophisticated data acquisition system, and a large liquid scintillator detector we find no evidence for 2.5 MeV neutron emission correlated with sonoluminscence from the collapsing bubbles. Any neutron emisssion that might occur is at least four orders of magnitude smaller than that necessary to explain the tritium production reported in Taleyarkhan et al. as being due to d–d fusion. We demonstrate that the proper allowance for random coincidence rates in such experiments requires the simultaneous measurement of the complex time-varying singles rates.