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There is a claim often made about cold fusion, that it is excluded theoretically. The main theoretical argument is that electronic energies are too low to overcome the Coulomb barrier, since d-d fusion only takes place at KeV energies, while chemistry is at eV energies.

This is belied by inner shells, which in Palladium store 3 or 20 KeV of energy per ejected electron, depending on whether the first or second shell is excited. These inner shell vacancies can decay either by x-rays, or by absorbing an electron into the vacancy and simultaneously ejecting a different electron (this second process is electrostatic). The cross section for ejecting a deuteron with tens of KeV's instead of an electron should be larger, since a deuterium is heavier. So I believe deuterated metal with excited inner shells has KeV deuterons running around.

If two KeV deuterons do a fusion to an alpha in a dense environment, close to a nucleus or to an electron, I don't know why the process cannot end without a proton or neutron ejected. There are electrostatic matrix elements that allow an unstable alpha-resonance to decay by giving its energy to a charged particle nearby, instead of ejecting a constituent.

After a fusion, the resulting alpha leaves an energetic track behind, and charged particles leave behind trails of atoms with ejected inner-shell electrons. So the K-shell holes produce fast deuterons, and fusion in deuterons produces K-shell holes. I don't see why this can't make a chain reaction.

I have explained this idea before. I would like to know whether somebody knows a sound theoretical argument which rules it out. Can such a chain reaction in a Pd be excluded theoretically? I am not asking if it is likely, I am asking whether it can be firmly theoretically excluded.

Anna v. asks how this process gets started--- it requires a random charged particle to pass through the deuterated material, from spontaneous environmental radioactive decay, or a cosmic ray muon. Charged particles produce K-shell holes.

To make my biases clear: I can't exclude it. Regardless of the quality of the experiments, I don't see an argument against cold fusion.

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and how are the K shell electrons kicked out of the k shell? – anna v Aug 4 '12 at 10:54
@annav: By the fast charged particles produced in the fusion process. To start the process, you need a cosmic ray, or random spontaneous charged particle produced by radioactivity in the environment, to produce an inner shell hole, then its self-sustaining. I said this in the question. – Ron Maimon Aug 4 '12 at 15:55
"and simultaneously ejecting a different electron (this second process is electrostatic). The cross section for ejecting a deuterium with tens of KeV's instead of an electron should be larger, since a deuterium is heavier".Deuterium is neutral, deuteron (the ion) is positively charged. Why would a neutral deuterium get involved in an electrostatic ejection in tandem with the absorption of the electron in the k-shell?. From what I know the deuteriums fill dislocations in the crystals, are interstitial. – anna v Aug 4 '12 at 16:56
@annav: I meant deuteron, I fixed it just now. The deuterons fill the interstitials, the electrons are just shared. The electrostatic process is always particle by particle, so it ejects electrons/deuterons at KeV energies, but the phase space for deuterons is bigger by a factor of 50 (although there are more electrons around than deuterons, also by a factor of about 50). – Ron Maimon Aug 4 '12 at 16:59
In that case one has to calculate the density of deuterons and the probability of meeting another deuteron to start the chain and sustain it.As fusion is a strong interaction and deuterons are interstitial, i.e. at electromagnetic distances, I would guess that there are orders of magnitude missing. – anna v Aug 4 '12 at 17:12
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