Robin, > "Since the H + D -> He3 reaction produces a 5.49 MeV gamma ray, it seems highly likely that this is what was observed, especially considering the fact that it is next to impossible to obtain pure D with no H content."
Yes. I think in retrospect that this was the reaction seen and documented, and not the D + D. Pardon my haste in that posting. In fact, as I was reconsidering the situation, I stumbled on another relating posting suggesting (via using the same Alvarez experiments) that the muon population could possibly be increased in effective lifetime in a Pd matrix, due to something approaching the argument used by Roarty to explain fractional hydrogen - time dilation. This was based on the paper "Phase Conjugation Feynman Diagrams" by Douglass A. White http://www.dpedtech.com/FD.pdf ..... and particularly the Feynman diagram of virtual, or time altered muon formation on page 7 and beyond, where the dominant muon decay diagram shows an energetic electron antineutrino "moving backward in time". What this diagram may indicate to some observers, i.e. if you are inclined to frame LENR (in part or totally) as muon (or tauon) catalyzed, is that there is a possible route to that conclusion, based on time distortion. "IF" that is, there is a fundamental change in "time" (rate of progression) which is based on confinement at very small dimensions. And there are many highly qualified observers making that argument. Given that the muon is ubiquitous in nature, due to cosmic rays - but also that they are extraordinarily short-lived - so as to be seemingly impossible to harness for catalytic fusion, one can look at how the decay could be influenced, or modulated, by the geometry of "tight quarters" so to speak. One far-out implication, based on other leptons like solar neutrinos, could be that muons NEVER really fully decay - in the sense of becoming unavailable to a reaction. Instead they merely experience "transformational decay" (or oscillation like neutrinos) from real to virtual - which can be analogized to nature "putting them in the Dirac freezer" for later use. Another way to say it, is several varieties of leptons oscillate between dimensions at the interface of the Dirac epo field. This might include the electron as well (to explain the FQHE). Anyway it is a fascinating prospect to reconsider, and only slightly less defensible than the currently favored hypothesis for LENR, which involves the time-delineated "spreading out" of ~24 MeV of energy into quadrillions of little packets - phonon ripples of heat (at a fractional eV each)... what I have been calling the "magic phonon" hypothesis. As an option to that, we now have am emergent "magic muon" hypothesis ;-) which can encompassed either the muon on tauon. In fact, magic muons can probably coexist with magic phonons. The wizardry of LENR... It's all about "time", bro... relatively speaking, that is .... Jones

