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8. Neutron Capture Is Not the New Cold Fusion
By Steven B. Krivit
Recently, a misunderstanding has arisen—only within the LENR field—over the terms "neutron capture" and "nuclear fusion." Some people are suggesting that "neutron capture" processes are a form of "nuclear fusion."
The problem surfaced in May 2009 when some "cold fusion" researchers attempted to convince others that the scientific concept of neutron capture processes could accurately be called fusion. Concurrently, they attempted to convince others that their claim of D+D cold nuclear fusion was justified by their suggestion and subsequent newly revised interpretation of the concept of nuclear fusion.
They abandoned both the nuclear physics definition of neutron capture and the nuclear physics definition of fusion.
Here are the New Energy Times concise definitions of the two concepts, derived from the Oxford Dictionary of Physics:
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Neutron Capture involves a single particle, such as a neutron, with no electric charge entering a nucleus.
Nuclear Fusion involves two nuclei having like-charges that overcome electrostatic forces (the Coulomb barrier). |
Origin of the Confusion
Nearly two decades ago, when the idea of neutron capture processes were more popular in the LENR field, there was no confusion about the distinction between neutron capture and nuclear fusion. (See "LENR Weak Interaction Theory—Hagelstein Missed" in this special report.)
As Peter Hagelstein, associate professor of electrical engineering at MIT, wrote in 1990: "No Coulomb repulsion occurs for virtual neutrons." The same is true for real neutrons.
Hal Fox, editor of Fusion Facts wrote in 1991: "Theorists like [Frederick] Mayer and Hagelstein, and Professor Yang of Hunan Normal University ... believe that what is occurring is a neutron transfer, not the fusion of two nuclei."
Three factors precipitated the recent confusion.
The first is the lack of progress on the part of LENR theorists and experimentalists in producing viable theories and rigorous evidence for LENR as a D+D "cold fusion" process.
The second factor is the growing recognition, since 2005, of the Widom-Larsen ultra-low-momentum neutron-catalyzed theory. These two factors brought things to a head for the LENR researchers who had supported the idea of D+D "cold fusion."
The third factor grew out of 2008 research published by the Navy SPAWAR group. For perhaps for the first time in at least a decade, researchers claimed experimental evidence of neutrons.[1] The SPAWAR claim is, thus far, not supported by conventional electronic detectors. Instead, characterization of neutron energies is based on interpolation from spatial measurements of particle tracks in solid-state nuclear track detectors.
However, New Energy Times is not aware of anyone who has suggested a conventional mechanism that explains how these particle tracks appear to traverse the full thickness of the detectors. We are not aware of any attempt to explain these events as anything other than neutrons.
Sporadic, low fluxes of neutrons were rigorously measured and reported in the field long ago, for example by researchers at Bhabha Atomic Research Centre in India. However, the flux of detectable neutrons is in no way commensurate with the excess heat that is measured in LENR cells if they are the result of thermonuclear fusion. Instead, the neutrons are presently useful for, among other things, confirmation of the reality of nuclear processes in LENR.
Following the neutron publication by this well-respected Navy laboratory, the American Chemical Society disseminated a press release about it on March 23, 2009. That, along with an ACS press conference, triggered a worldwide wave of interest in "cold fusion," possibly unprecedented since 1989.
Dueling Dictionaries
Nobel prize-winner Brian Josephson, a D+D "cold fusion" advocate, and Lewis Larsen, co-developer of the Widom-Larsen "not-fusion" theory, fought a fierce war of words on a CBS-TV blog. Josephson was advocating that the definition of fusion "to join or become combined," from "the dictionary" (he didn't specify which one), include neutron capture.
Larsen, however, advocated the definition of "nuclear fusion" from the Oxford Dictionary of Physics.
The disagreement spilled over into the members-only CMNS e-mail list for LENR researchers. Other theorists began to follow the neutron capture lead.
On April 26, theorist Andrew Meulenberg announced to the CMNS list his "Modest Proposal" for new mechanisms to explain D+D "cold fusion." Meulenberg proposed that "energetic electrons within the nuclear region enhance the probability of one of the protons becoming a neutron."
On May 19, Russian researcher Fangil Gareev announced to the CMNS list his "New Mechanism of Cold Fusion Reactions," in which an electron somehow reacts with a deuteron and produces a new imaginary particle, dineutroneum, as well as a phonon. Gareev's concept was akin to the second step in the Widom-Larsen process. Gareev told New Energy Times that his colleague Yuri Ratis had developed a mathematical model for the theory and had published it in Russian, though he did not state where.
A week earlier, on May 11, Josephson reiterated his definition of fusion to the members of the CMNS list.
"I hope people will agree with me that blandly coming out with the statements such as 'fusion is not involved' should be considered bad practice," Josephson wrote.
American theorist John Fisher, who has developed a neutron capture model of LENR, corrected Josephson and SRI International electrochemist Michael McKubre, who had also entered the fray.
"The process could be called 'fusion' in Mike's sense," Fisher wrote, "but this would not be acceptable to physicists who already have settled on ‘neutron capture.’"
McKubre replied to Fisher.
"[I] don't see any need why we should be frightened off by physicists' jargon usage of the word fusion," McKubre wrote. "The high energy and particle physicists don't own the word in our context. In the future we will."
McKubre followed that post with another generic definition of the word fusion and a message to his colleagues in the field. (Source image)
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Folks, I have a contribution about definition.
It is true that a number of our physics colleagues are strongly opposed to the phrase 'cold fusion,' but I have always thought that this is because they have internalized an over-restricted (and over-possessive) use of [the word] 'fusion.'
As the dictionary states, this is a shorthand for nuclear fusion, but it seems to have been restricted even further to mean (in their minds exclusively to mean) the pairwise fusion of light isotopes – specifically Li and D – by a particular mechanism. I find this to be a limited jargon usage at the point of banality, and I wonder why we bother to argue.
First, look at the definition: 'The process or result of joining two or more things together to form a single entity.' I submit that D + D –> 4He qualifies (whereas pairwise collisional hot fusion via the normal branches might not. ...). I also submit that John's neutron addition reactions also qualify as fusion. We are certainly not bound to use the jargon of particle physics and should not! We are free to use the English language (I suspect this definition is similar in most), without apology or deference, so long as we use it correctly.
A more subtle point is the presumption of mechanism. In thermodynamics, one is concerned with initial and final states only! The pathway (mechanism) is just important for rate predictions (and we are a long way from that). The fusion 'purists' (with their corrupt definition) want ownership of the products and process. However, to re-coin a phrase, 'the circumstances of cold fusion are not those of hot fusion.' Whatever reaction we are studying could (I would argue must) undergo a very large number of steps involving a very, very large number of participant species. But for definition, this is not important. Is the final state the result of 'joining two or more things together'? If yes, then I submit it is fusion. If it is spontaneous, then it is exothermic. If it is exothermic, then it consumes mass.
–Mike
P.S. One reason the critics are concerned about naming is to get us involved in a trap of circular reasoning that proceeds something like this. If it is fusion, then it is 'our' (hot) fusion, then you must see 'our' rates and products, which you don't, so it is not. You can all see the flaw, and by now I would hope we could ignore this scarecrow made of very poor straw. |
As an interesting side note, in 1996 McKubre thought it unlikely that fusion was occurring in his heavy-water cells and certainly not in the light-water cells.
LENR researcher Dennis Cravens commented next on the CMNS list:
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I am not sure what the definition of fusion is, but if we put deuterium into the system and get helium out, we have increased the [atomic number]. The process of how that is done doesn't seem to be important to the definition. There may be many ways to achieve it. The net effect is we have increased the [atomic number] and the mass. Sure seems like fusion to me. To me, fusion [is] just producing a product with higher [atomic number] and mass than the reactants. |
New Energy Times received another interesting idea about the concept of fusion from a LENR researcher whom we agreed to quote anonymously:
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In my view, if palladium absorbs a neutron, it becomes unstable. It then gives off an electron and becomes silver. Is this fusion or transmutation? The silver nucleus has one more proton than the palladium atom from which it was produced. So we can say that the neutron fused into the palladium nucleus, causing it to transmute to silver. |
Another response on the topic came from LENR-CANR librarian Jed Rothwell:
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I think you are silly for saying it may not be fusion. Of course it's fusion! Heat + Helium production = Fusion. Case closed. I have no idea how those deuterons fuse, but I am sure they do. I cannot judge. However, I am sure that any process that converts deuterium to helium and produces heat is fusion, by definition. |
These "cold fusion" advocates did not understand that helium-4 could be produced by a wide variety of reactions, only one of which was DD fusion.
Reference
1. Mosier-Boss, P.A., Szpak, S., Gordon, F.E., and Forsley, L.P.G., "Triple Tracks in CR-39 as the Result of Pd–D Co-deposition: Evidence of Energetic Neutrons," Naturwissenschaften, Vol. 96, pp. 135-142, (Oct. 1, 2008)
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