Editing Cold fusion (section)

===Helium, heavy elements, and neutrons===
[[File:Triple tracks in CR-39.jpg|right|thumb|"Triple tracks" in a [[CR-39]] plastic radiation detector claimed as evidence for neutron emission from palladium deuteride]]
Known instances of nuclear reactions, aside from producing energy, also produce [[nucleon]]s and particles on readily observable ballistic trajectories. In support of their claim that nuclear reactions took place in their electrolytic cells, Fleischmann and Pons reported a [[neutron flux]] of 4,000 neutrons per second, as well as detection of tritium. The classical [[Branching fraction|branching ratio]] for previously known fusion reactions that produce tritium would predict, with 1 [[watt]] of power, the production of 10<sup>12</sup> neutrons per second, levels that would have been fatal to the researchers.<ref>{{harvnb|Simon|2002|p=[https://archive.org/details/undeadsciencesci0000simo/page/49 <!-- quote=Voodoo science. --> 49]}}, {{harvnb|Park|2000|pp=[https://books.google.com/books?id=xzCK6-Kqs6QC&pg=PA17&dq=neutron+neutrons+tritium+gamma+rays 17–18]}}, {{harvnb|Huizenga|1993|pp=7}}, {{harvnb|Close|1992|pp=306–307}}</ref> In 2009, [[Pamela Mosier-Boss|Mosier-Boss]] et al. reported what they called the first scientific report of highly energetic neutrons, using [[CR-39]] plastic radiation detectors,<ref name=MosierBoss2009>{{harvnb|Mosier-Boss|Szpak|Gordon|Forsley|2009}}, {{harvnb|Sampson|2009}}</ref> but the claims cannot be validated without a [[Quantitative analysis (chemistry)|quantitative analysis]] of neutrons.{{sfn|ps=|Barras|2009}}{{sfn|ps=|Berger|2009}}

Several medium and heavy elements like calcium, titanium, chromium, manganese, iron, cobalt, copper and zinc have been reported as detected by several researchers, like [[Tadahiko Mizuno]] or [[George H. Miley|George Miley]]. The report presented to the [[United States Department of Energy|United States Department of Energy (DOE)]] in 2004 indicated that deuterium-loaded foils could be used to detect fusion reaction products and, although the reviewers found the evidence presented to them as inconclusive, they indicated that those experiments did not use state-of-the-art techniques.{{sfn|ps=|US DOE|2004|pp=3, 4, 5}}

In response to doubts about the lack of nuclear products, cold fusion researchers have tried to capture and measure nuclear products correlated with excess heat.{{sfn|ps=|Hagelstein|2010}} Considerable attention has been given to measuring <sup>4</sup>He production.{{sfn|ps=|Hagelstein|McKubre|Nagel|Chubb|2004}} However, the reported levels are very near to background, so contamination by trace amounts of helium normally present in the air cannot be ruled out. In the report presented to the DOE in 2004, the reviewers' opinion was divided on the evidence for <sup>4</sup>He, with the most negative reviews concluding that although the amounts detected were above background levels, they were very close to them and therefore could be caused by contamination from air.{{sfn|ps=|US DOE|2004|pp=3,4}}

One of the main criticisms of cold fusion was that deuteron-deuteron fusion into helium was expected to result in the production of [[gamma rays]]—which were not observed and were not observed in subsequent cold fusion experiments.{{sfn|ps=|Schaffer|1999|p=2}}{{sfn|ps=|Rogers|Sandquist|1990}} Cold fusion researchers have since claimed to find X-rays, helium, neutrons{{sfn|ps=|Simon|2002|p=215}} and [[nuclear transmutation]]s.{{sfn|ps=|Simon|2002|pp=150–153, 162}} Some researchers also claim to have found them using only light water and nickel cathodes.{{sfn|ps=|Simon|2002|p=215}} The 2004 DOE panel expressed concerns about the poor quality of the theoretical framework cold fusion proponents presented to account for the lack of gamma rays.{{sfn|ps=|US DOE|2004|pp=3,4}}