Eric, Lots of good, but very difficult questions.
I am trying to understand how Compton scattering formulas change when dressed electrons are involved. I do not think the standard derivations work for electrons in e-m fields - whether bound or not. Even fields in dc currents probably cannot be ignored. Experimental results are hard to find. This effect may be related to the interpretation of the magnetic vector potential as a store of momentum - see: "What the electromagnetic vector potential describes" www.uccs.edu/~jmarsh2/links/AJP-46-05-499.pdf Yes, if the paper is correct and NAEs occur in volumes where dressed electrons are densely distributed, then maybe any gammas generated will quickly dissipate most of their energy in collisions before escaping. Perhaps NAEs are sites where large field energies "dress" electrons, protons and nuclei. My guess is that ultra-high energy nonlinear effects like some types of pair creation are unlikely, but I am not sure. I do believe that the protons will oscillate coherently in surface plasmons. Also, note that MarkI-ZeroPoint has continued this tread renamed as - [Vo]:How to modify cross-sections and branching ratios. -- Lou Pagnucco Eric Walker wrote: > Lou, > > Interesting paper. The conditions explored in the paper, if I've > understood them, are the Compton scattering of high energy photons on > hydrogen atoms in the midst of a low energy laser field. The energy of > the > laser field is significantly below that of a typical transition frequency > of the target electron in the ground state. To make things concrete, I > take this to mean much less than the ionization potential of hydrogen, > 13.6 > eV; so significantly greater than 91 nm, in the ultraviolet range. > > This situation might be a good lower bound for the kind of photon field > that would arise in the nuclear active area leading up to or following > upon > a reaction. My reading of the qualitative sections of the paper suggests > that even at the lower bound, funny things happen. Two additional quotes > worth mentioning: > > "We will see, however, that not only the electron spectra can be > dramatically modified by the coupling with a relatively weak laser field > but also that this field may noticeably influence the properties of the > outgoing high-energy photon." (p. 8.) > > "The main effect of the laser field is the shift of the maximum in the > photon energy spectrum towards lower frequencies." (p. 11.) > > > It will be a while before I am able to make use of the field theory > equations, unfortunately (or perhaps fortunately). Three questions arise: > (1) How relevant are the initial conditions of the paper to the state of > the nuclear active environment at any point in its evolution? (2) How > accurate is the model developed in the paper for what it's exploring? (3) > And what are the constraints that the model, if accurate, places on what > we > are considering? > > From what I have read of some other papers recently, at higher energies > some additional processes arise: > > - Hard photons (far greater than 511 keV) scatter off of soft photons > (far less than 511 keV), yielding electron-positron pairs in a > successive > cascade of interactions, losing energy in the process. > - Hard photons scatter off of electrons and positrons. > - Hard photons scatter off of one another. > - Accelerating protons yield pairs, giving off energy and providing > additional targets for hard photons. > > If the circumstances are right, the "optical depth" of the hard photons > can > reach 1, in which case the "catastrophic loss" of the hard photons, or > their exit from the volume representing the system, reaches zero. The > circumstances for such an optical depth are remarkably stable and > attainable in the cosmological case provided there's a magnetic field. > The > tricky part is that for at least one equilibrium condition the magnetic > field must be high for hard photons in the lower range (at or above 300 > MeV). The magnetic field is what gives rise to the pair production in the > several equilibrium conditions that are seen to result in the complete > absorption of hard photons. I think there is another equilibrium > condition > that does not depend as much upon the magnetic field. Some rather > exciting > graphs describe these equilibrium conditions: > > Figure 5, page 6, of http://arxiv.org/pdf/1105.3852.pdf. I think the > graph > says that when the "compactness" of the luminosity of soft photons and > hard > photons is equal, anything above 10^4 eV disappears from the spectrum, > except for a sharp peak. I do not know how to interpret the peak; it > could > be the 511 keV of the electron-positron annihilation photons, although I > think it is too far to left for this. > > Figure 1, page 10, of http://arxiv.org/pdf/astro-ph/0701633.pdf. Here the > regions above the solid black line are ones in which complete hard photon > absorption arises. > > > These graphs are for the cosmological case. I get the impression the > gamma > quenching is taken as a given for certain astrophysical systems and is not > controversial. I'm hoping I can tease apart the models that are used for > these calculations like one might disassemble a watch and then put them > back together and see if equilibrium conditions are possible for lower > energies and weaker magnetic fields. > > The system in my mind at this point is that of a volume of ionized protons > being propelled by high energy photons with enough energy to accelerate > them significantly and cause them collide with deuterium and helium > nuclei. Perhaps on occasion the collisions are sufficient for fusion, > resulting in the injection of additional hard photons into the cavity and > the maintenance of a field of soft photons and other targets sufficient to > cause the hard photons to completely scatter. One question I have is > whether a nonthermal distribution of protons that are in synchrony with > the > cavity mode would ever be possible. > > Eric > > > On Thu, Jul 5, 2012 at 11:06 AM, <[email protected]> wrote: > > Eric, >> >> It appears that the photon-stopping power of electrons which are >> "dressed" >> in electromagnetic fields may be much greater than that of bare >> electrons >> - i.e., "dressed" electrons that are exchanging large numbers of virtual >> photons with nearby nuclei and other electrons in magnetic and coulomb >> interactions. See: >> >> " On Compton scattering of energetic photons by light atoms in the >> presence of a low-frequency electromagnetic field" >> >> >> http://pubman.mpdl.mpg.de/pubman/item/escidoc:919561:1/component/escidoc:919560/COMPT777.pdf >> >> The gist of the paper is stated on page 3: >> "...that spectra of both emitted electrons and scattered photons can be >> remarkably modified by the interaction with a weak low-frequency laser >> field." >> >> Perhaps even greater effects occur in intense e-m fields generated in >> carbon and metal nanostructures. >> >> However, since gammas would not even be generated in some proposed LENR >> theories (e.g., neutron capture), this may be moot. >> >> I have some more data, but not enough time to post it right now. >> >> -- Lou Pagnucco >
