We have conducted a search for neutron emission from cold fusion systems of the electrochemical type and, to a lesser extent, the high‐pressure gas cell type. Using a high‐efficiency well counter and an NE 213 scintillator, the experiments were conducted on the earth’s surface and in a shielded cave approximately 50 ft underground. After approximately 6500 h of counting time, we have obtained no evidence for cold fusion processes leading to neutron production. However, we have observed all three types of neutron data that have been presented as evidence for cold fusion: large positive fluctuations in the neutron counting rate, weak peaks near 2.5 MeV in the neutron energy spectrum, and bursts of up to 140 neutrons in 500‐μs intervals. The data were obtained under circumstances that clearly show our results to be data encountered as a part of the naturally occurring neutron background, which is due primarily to cosmic rays. Thus, observing these types of data does not, of itself, provide evidence for the existence of cold fusion processes. Artifacts in the data that were due to counter misbehavior were also observed to lead to long‐term ‘‘neutron bursts’’ whose time duration varied from several hours to several days. We conclude that any experiments which attempt to observed neutron emission must include strong steps to ensure that the experiments deal adequately with both cosmic‐ray processes and counter misbehavior.

This paper reports a collaborative effort of a team which formed at Los Alamos to investigate the announcement that “cold fusion” may be occurring in electrochemical cells using palladium cathodes and platinum anodes in a LiOD electrolyte. Four electrochemical cells were construced and operated for 3–5 weeks under various geometrical and electrical conditions. Nuclear diagnostic measurements included high and low resolution gamma-ray spectroscopy, integral neutron counting with well detectors and banks of3He tubes, and neutron spectroscopy withNE-213 scintillators. For one of the cells, the deuterium loading of the cathode was determined from resistance measurements to beD/Pd⩽ 0.8. No conclusive evidence was found for the production of neutrons or 2.223-MeV gammas above levels consistent with background. The results of the measurements of tritium levels in the cell electrolytes are also reported. Experiments to reproduce the observation of neutrons from high pressureTi-D2 gas experiments were also performed with negative results.

We have cxmducted a iwarch for neutron emiosion fmm m)d fusion systems of the electrochemical type and, to a leeser extent, the high-pressure gag cell type. Using a high-efficiency well counter and an NE 213 scintillator, the experiments were czmducted on the earth's ~urfam and in a shielded ave approximately 50 ft under-g-round, After appmmimately 6.500 h of counting time, we have obtained no evidence for cold fusion prucesse.~ leading h neutron production. However, we have observed all three types of neutron data that have been presented as evidence for cold fusion: large positive fluctu.utiona in the neutron counting rate, weak peaks near 2.6 MeV in the neutron energy spwtrum, and bumts of up to 146 neutrons in W30-IJS intel vals. The data were obtained under circumotancm that clearly show our reeulta to be dab encounter as a par-t of the ")aturally oczuning neutron background, which io due primarily to cosmic raya, ThuE, observing these types of data does not, of itself, provide evidence for the existence of cold fusion prcnxwes. &-tifac~u in the data that were due to counter misbehavior were also observed to lead ta long-term "neutron bumts" whose time d wation varied from several hours to several days We conclude that any experimertu whicl~ attempt to observe neutron emission must include strong steps to ensure that the eqw-imenta dael adequately with both cosmic-ray processes and coutir misbehavior,