Upper limit for neutron emission from cold d-t fusion

Reports that fusion of hydrogen isotopes may occur at room temperature during the electrolysis of D2O led us to investigate possible d-t fusion reactions in an electrolysis cell with a tritiated Ti cathode. A searc for 14-MeV neutrons from this reaction, using an NE213 scintillator detector and pulse shape discrimination techniques, showed no significant deviations from background levels. We derive an upper limit of 10-23 s-1 for the fusion rate per d-t pair.