Wikiversity/Cold fusion/Theory/Ron Maimon Theory
The idea of this theory is that the reaction is a chain-reaction of d-d fusion happening close to the Pd nucleus, through a mechanism of excitation of inner shells.
The inner-shell holes are excited by the charged particles produced in this process, these charged particles zip through the metal at ~20MeV, making about 300 K-shell holes, and more lower-energy excitations too. About half of these holes then accelerate 150 deuterons by the Auger mechanism, the same mechanism that leads electrons to become accelerated as inner shell holes are filled. These 150 deuterons are zipping aruond at 20KeV, and in the confines of the metal, they can fuse, making more K-shell holes, and accelerating more deuterons, thus sustaining the chain reaction.
This process is theoretically marginally viable, in the sense that it is close to a chain reaction with no fudging, using known rates for processes at 20KeV, but it is not compatible with the experimental results reported during excess heat events. The reason is that there is a tight bound, the Hagelstein bound, from secondary neutrons produced by nuclear collisions, which excludes the He4 produced from being born with 24 MeV, rather, this suggests that any nuclear process must occur in a distributed resonant way over many atoms, so that the 24 MeV is shared broadly. This is the focus of Hagelstein, and he has made some progress in producing models which have the ability to do this. The remainder of this article is correct in saying that the process is close to self-sustaining, and that the effects are consistent with the trace radiological events in cold fusion experiments, but it is not correct in saying that it matches the phenomenon, because it predicts fast particles, and much more neutrons and secondary radiation that what is observed.
The accelerated deuterons have a classical turn-around point very close to the nucleus, and they flow through the metal as a charged conducting fluid, at around 20KeV in each particle, and they can flow a ways before relaxing. They can't melt the crystal, because they have just too little energy to knock a nucleus out of position (they have the same energy as a K-shell hole, which can't knock a nucleus out of it's spot either). When these deuterons are concentrated enough in a region, their wavefunction piles up right next to the Pd nuclei, and there, they fuse, and they transfer the energy of the fusion reaction electrostatically to the Pd nucleus. This is a theoretically allowed process, it is enhanced by the large charge on Pd, and it has never been observed, simply because there is no other configuration which allows two deuterium nuclei to come close to another nucleus at the moment they fuse, so there is no reliable estimator of rate, except that it's not too far from ordinary d-d fusion.
For the chain-reaction to be self-sustaining, about 1 in 100 of the accelerated d's needs to fuse. The rate of hot beam fusion for a beam shining at 20KeV on deuterated Pd is about 1:10,000, so the three body effect has to be about 1-2 orders of magnitude more efficient than ordinary dilute-beam fusion, and this is easily be attributed to the resonance structure of the alpha-particle, since not every resonance can contribute to the ordinary fusion cross section due to the Isospin, angular momentum, and parity conservation in free space. These conservation laws are out the window when a nucleus is nearby.
The theory predicts all the observed effect:
- X-ray emission (from K-shell holes that decay electrostatically)
- Sporadic hot fusion at small rates (because two 20KeV deuterons have a non-negligible hot-fusion cross section).
- Emission of He commensurate with heat.
- transmutations of the Pd nucleus.
The transmutations happen because 10MeV energy transfer is known to break a Pd nucleus. The pattern of breaking of Pd by electrostatic energy transfer of 10MeV is known from electron LINAC experiments, and it is very characteristic: the nucleus is only marginally unstable, and tends to eject highly stable closed shell nuclei: He4, C12, O16. Sometimes, other even number nuclei come out, but at lower rates. These transmutations look like losing an integer number of alpha particles, and these are precisely the type of light elements which are produced in trace results in the transmutation experiments of Iwamura et al. The Pd looks like it fissions to 100-4n and 4n in equal amounts. There are other mass-spec things that look like molecules of the fission products, and molecules of these type of ejecta will explain everything that everyone reliably saw using mass-spec.
The ejected alphas and the fusion alphas are both travelling at order 10MeV energy, and can be absorbed in transit by another nucleus, leading to +1,+2 radiological contamination, explaining the radiological results of Wolf and others. There can also be rare +8, +12 transmutations from pickup of an ejected He,Be fragment, but these mass-spec results it is safer to attribute to molecules.
The prediction for X-rays is simply at comparable to the excess heat, since the amount of energy in K-shell holes is comparable to the excess heat, up to one order of magnitude. So the X-ray emissions are some watts per second. This is consistent with the observations of Mosier-Boss and SPAWAR, weak X-ray emissions while excess heat is produced. Any X-ray collimation is just due to diffraction by the crystal.
The theory predicts Auger deuterons, which is a safe prediction, but it has not been made before. It predicts the same effect in any metal which can be heavily deuterated with an inner shell excitation at around 20KeV or more, depending on resonance details. It also predicts that Ni-H cold-fusion is impossible, simply because the only way to have this is by d-p fusion, and the amount of deuterium in ordinary water is too small for the d's to be accelerated in sufficient numbers--- the maximum number of accelerated deuterons in Nickel for each fusion is about 3, and it is absurd to think that the reaction rate is 1 in 3.
This theory has no ad-hoc theoretical assumptions, and it is consistent with some of the data, but it predicts too many incoherent neutrons from the fast charged particles, and is excluded by Hagelstein's analysis of the limits on energy of the He nuclei produced.