I recently came across the concept of photobeta decay. Photoneutron or Photoproton decay is a well known process which occurs when very high MeV photons of sufficient energy and characteristics interact with nuclei and can result in the emission of Protons or Neutrons providing the associated Q value for emission is reached. Photobeta decay is a similar process whereby a photon of sufficient energy and characteristics interact with and can result in the emission of Beta providing the associated Q value for emission is reached. Photobeta decay was looked at in the 1960's by P. B Shaw, D.D. Clayton and F.C. Michel as a possible process occurring in the Nucleosynthesis process in Red Giant stars and has been used along with the r-process and s-process of neutron capture to explain the element abundances of some heavier elements. I have not found many literature of photobeta decay in other more recent contexts though. Obviously the core of a red Giant is not a normal environment so it maybe a bit special there. These papers are paywalled unfortunately but the second one you see part of it in preview http://journals.aps.org/pr/abstract/10.1103/PhysRev.140.B1433 http://rd.springer.com/article/10.1134%2F1.1788033 I wonder if something similar can occur in more normal environments or in LENR active sites etc. Some elements have quite low Q values for beta decay, these include Ni63 for example which has a Q value of 66.977 keV and decays with a long half-life of 101 years to Cu63 which is stable. Cu63 then has a correspondingly low negative Q value of -66.977 keV for Beta + decay or Electron capture. Since all Q values for Cu63 are negative it is normally stable. (note Ni63 is not a natural abundant element of Nickel due to its half life of 101 years) It has been reported that we may get broad spectrum X-ray radiation in some devices such as seen by MFMP in their GS 5.2 experiment. This spectra is bremsstrahlung like in that it has low intensity at high energies and increases to much higher intensities at lower energies especially from around 100 keV and below. I wonder what happens to these nuclei with low + and - Q values when they are in this kind of broad spectrum environment including X rays at 66.955 keV? Could Ni63 be stimulated to beta decay at a faster rate that half-life of 101 years?Could normally stable Cu63 be stimulated to compensate for the -Q of -66.977 keV and undergo Beta + decay or electron capture? If this strange scenario is possible then we could the Ni63/Cu63 effectively cycle thereby generating energetic beta by absorbing gamma or X-rays of 66.977 keV? One way to check for this I suppose is to see if any Ni63 was present in the ash (perhaps by detecting Beta radiation with a Q value of 66.977 keV). There are not many normal possible sources of Ni63: If proton absorption is occurring with Ni62 then it would form Cu63 which is normally stable. If Neutron absorption occurs then it could also be possible generated from neutron absorption in Ni62 but then maybe we would expect other elements or isotopes to have consistent signatures of neutron absorption. If Ni63 and/or Cu63 can undergo Photobeta decay (a big if admitably) some other elements and isotopes with Q values below 100 or so keV could be implicated. Such as: Pb210/Bi210 : Qbeta = 63.486 keV (side note: this is a Radon Progeny)Pd107/Ag107: Qbeta = 34.078 keV (side note: Ag 107 is stable and has a isomer at 93.125 keV) H3/He3: Qbeta = 18.591 keV There are several more < 100 keV and many more < 500 keV Interestingly at frequencies below 100 keV they are also close to the K alpha and K beta characteristic X-Ray emission frequencies from the inner shell electron transitions of some heavier elements such as Tungsten (W)
