The Rossi collective seem to be convinced, or at least promoting the hypothesis that the fusion of a proton with nickel, resulting in copper, is the main heat source in this device.
There are other options. One possibility is related to dense hydrogen or "pycno". This could include Miley's inverse Rydberg hydrogen or the less dense variety. Here is an important Miley paper where he sees clusters of about 100 atoms in a "defect" . (Casimir cavity ??) http://iopscience.iop.org/1742-6596/244/3/032036/pdf/1742-6596_244_3_032036. pdf Inverse Rydberg states of hydrogen atoms are far denser than 100 atoms, of course, and relatively "long-lived". Here is the citation (fee) - if it is confirmed by other experimenters, then it could be one of the most important papers in LENR: "Ultrahigh-density deuterium of Rydberg matter clusters for inertial confinement fusion targets" L. Holmlid, H. Hora, G. Miley and X. Yang, Laser and Particle Beams 27 (2009) 529-532. Holmlid, Miley and associates, claim that the density seen in their testing works out to the equivalent of ~10^29 atoms/cm^3, which more than enough for the "solar variety" of proton-proton tunneling reaction (or chain reaction) which is one of the prime fusion reactions by which stars convert hydrogen to energy. The proton-proton chain reaction dominates in stars the size of our Sun or smaller, which are in this range of density. In 1939, Hans Bethe proposed that one of the protons in this reaction will beta+ decay into a neutron via the weak interaction during the fusion, making deuterium as an initial product in the chain that leads to helium - and he won the Nobel Prize, in part for this insight. It adds new meaning to one of the early idioms for cold fusion - "sun in a bottle". In reading Ed Storms recent musings, he seems to favor a rare version of this H+H reaction for Rossi - one that does not involve extreme density - known as the P-e-P reaction, which also results in deuterium, as the 'ash'. However, if we add the Holmlid/Miley finding into the mix - extremely dense IRH (inverse Rydberg hydrogen) or even the 100 atom cluster, then we can possibly stay with better known solar reaction, involving beta+ decay. The falsifiability of this hypothesis can be related to the appearance of deuterium and perhaps the gamma signature of the positron, as it either annihilates or goes to positronium with the UV signature (6.8 eV). This kind of fusion is consistent with all we know if the copper is explained as migration or occasional fusion. Furthermore, the 'catalyst' of Rossi could changing gaseous hydrogen via spillover, into dense deuterium, or even IRH. The catalyst is the breakthrough, and my take on it is that it is a spillover catalyst and possibly it is the same NaH which is used by Mills. That would be powerful incentive Jones
