sCIENCE OF COLD FUSION
| Cold fusion was first announced on March 23, 1989 when Professors Martin Fleischmann and Stanley Pons reported producing nuclear fusion in a tabletop experiment involving electrolysis of heavy water on a palladium (Pd) electrode. They reported anomalous heat production ("excess heat") of a magnitude that defied explanation except in terms of nuclear processes. They further reported measuring small amounts of nuclear reaction byproducts, including neutrons and tritium. These reports raised hopes of a cheap and abundant source of energy. Indeed the story of cold fusion has been reported as being the most intensively televised story in the history of TV! |  |
Martin Fleischmann of the University of Southampton and Stanley Pons of the University of Utah hypothesized that the high compression ratio and mobility of deuterium that could be achieved within palladium metal using electrolysis might result in nuclear fusion. To investigate, they conducted electrolysis experiments using a palladium cathode and heavy water within a calorimeter, an insulated vessel designed to measure process heat. Current was applied continuously for many weeks, with the heavy water being renewed at intervals. Some deuterium was thought to be accumulating within the cathode, but most was allowed to bubble out of the cell, joining oxygen produced at the anode. For most of the time, the power input to the cell was equal to the calculated power leaving the cell within measurement accuracy, and the cell temperature was stable at around 30 °C. But then, at some point (and in some of the experiments), the temperature rose suddenly to about 50 °C without changes in the input power. These high temperature phases would last for two days or more and would repeat several times in any given experiment once they had occurred. The calculated power leaving the cell was significantly higher than the input power during these high temperature phases. Eventually the high temperature phases would no longer occur within a particular cell.
Scores of laboratories in the United States and abroad attempted to repeat the experiments. A few reported success, many others failure. Even those reporting success had difficulty reproducing Fleischmann and Pons' results. One of the more prominent reports of success came from a group at the Georgia Institute of Technology, which observed neutron production. The Georgia Tech group later retracted their announcement. Another team, headed by Robert Huggins at Stanford University also reported early success, but this too was refuted. For weeks, competing claims, counterclaims and suggested explanations kept what was referred to as "cold fusion" or "fusion confusion" in the news.
In May 1989, the American Physical Society held a session on cold fusion, at which were heard many reports of experiments that failed to produce evidence of cold fusion. At the end of the session, eight of the nine leading speakers stated they considered the initial Fleischmann and Pons' claim dead.
In April 1989, Fleischmann and Pons published a "preliminary note" in the Journal of Electroanalytical Chemistry. This paper notably showed a gamma peak without its corresponding Compton edge, which indicated they had made a mistake in claiming evidence of fusion byproducts. The preliminary note was followed up a year later with a much longer paper that went into details of calorimetry but did not include any nuclear measurements.
more to come...