Present Status Of Cold Fusion Experiment at KEK

Abstract

Since spring of 1989 we have attempted to confirm the so-called cold fusion phenomena by detecting excess heat and various nuclear products, usingopen type electrolysis cells. A variety of cells containing Pd (cathode)/0.1M LiOD/Pt (anode) were examined, but recently efforts have been concentratedon dewar type cells containing a small palladium cathode, about 2mm∅×7mm in size. Until now a burst-like heat release, equivalent to 110% of theinput electric power, was observed in one cell, with neither increase of neutronemission nor that of tritium concentrations. Helium was observed, but nodecisive conclusion could be drawn due to incompleteness of the then used detecting system. In another experiment an abnormal increase of neutron emission, about 3.8σ above the background level, was observed with neither coincidentalheat burst nor tritium anomalies. It lasted for 9 hours and the emission ratethat amounts to 27.2±11.2 neutrons s-1 was 700 times as much as the background level. It happened also only once, which makes the possibility of thesystem error negligible and paradoxically supports its reality. In the otherexperiment abnormal emission of the low energy (below 20 keV) X-ray hasbeen detected during the D+ charging period, indicating some type of nuclearphenomena may be happening in the cell. Further studies as well as reproductions of the anomalies are becoming highly essential to understand totallythese abnormal phenomena.