If I put on my Don Hotson hat and *-try-* to consider his description of the proton, neutron, and the strong force, could it provide some insight? Hotson considers that protons and neutrons are composed of epos, in an orthogonal condensate in 10 dimensions. There are no quarks - just the electron-positron pairs in degenerate orbit (an epo). The hard diameters of the proton and neutron are essentially set by the orbital radius of the epo (something like 1.8 fm if I recall); as the nucleons approach closer than this, the "strong force" becomes a hard repulsive force as the epos run into each other. A proton has a positive charge because it has a nucleon valence electron hole in its 10 dimensional condensate of epos and a neutron is neutral because it has an equal number of full epos. When the neutron and proton approach each other, the strong attractive force is the exchange force as an epo begins to orbit back and forth between the proton and neutron (in analog with electron exchange in chemical bonds between nuclei). In this exchange, the nuclear valence electron hole can switch between the two nucleons, causing the charge to switch back and forth - an apparent switch of each nucleon between proton and neutron.
In conventional nuclear theory, there is a bad conflict between the measured nucleon density and apparent orbital magic-ness. From measurements, nucleons appear to be too tightly packed to actually orbit a common center of mass. So how can there be "orbital-like magic-ness" in the nuclear binding force? It is electron orbital magic-ness that gives us the periodic table - the magic-ness causing resonances in chemical molecular binding. But with the nucleons too tightly packed to orbit in the conventional sense around the nucleus center of mass, it is still possible that the nucleons have "virtual" orbiting, even if the nucleon centers are fixed into a lattice. In a lattice, the epo exchange coupling can produce resonances around and through the lattice to bind the nucleons (into a lattice). It can appear that a proton is orbiting the lattice because it is changing into a neutron and its adjacent nucleon changes to a proton; a process that continues around the lattice in a resonant ring (for example). Imagine in a nuclear lattice how many orthogonal exchange resonances like this could occur - it will depend on the number of nucleons. These exchange force lattice resonances may provide the observed magic-ness in the nuclear binding force. This is my extension of Hotson's description of the nucleons and their binding. Is it possible to take this non-conventional "understanding" of the nucleus and apply it to the interaction you are describing? Bob Higgins On Mon, Sep 28, 2015 at 9:56 AM, Eric Walker <[email protected]> wrote: > Hi, > > I just read about an interesting characteristic of the nucleon-nucleon > interaction (e.g., the scattering of a proton with a neutron or a proton > with a proton or a neutron with a neutron). I wonder whether this > characteristic is behind what we've been referring to here as "neutron > tunneling" or "neutron stripping" in earlier posts to this list. > > This characteristic is called the "one pion exchange potential," and it > can be seen in low-energy neutron-proton scattering experiments (< ~ 20 > MeV). In these experiments a neutron becomes a proton and a proton becomes > a neutron through the exchange of a charged pi meson, or pion. In the > scattering experiments the pion is not a real pion but a virtual one, > limited by the constraints of the uncertainty principle. For this reason > it has a very short range, on the order of femtometers, which is the range > at which nuclear reactions take place. > > To see how virtual pion exchange works in an experimental context, > consider a neutron that is incident upon a proton. The outgoing neutron > will scatter in any number of angles, with differing probabilities. A > likely scenario is that the neutron will scatter at a small angle -- some > angle close to 0 degrees, for example. In these cases the neutron is > deflected a little bit from its initial trajectory. In other cases it will > scatter into a larger angle, perhaps up to 90 degrees or more. These > outcomes are seen less and less at larger angles. > > Where things get weird is that beyond a certain angle the probability > starts to increase again and reaches a maximum comparable to the small > scattering angles. To the observer this looks as though what is happening > is that the neutron is incident upon the proton, and the neutron transfers > all of its momentum to the proton, and the proton then leaves the > scattering along a trajectory similar to the one in which the neutron > entered it. These interactions occur with a probability that is comparable > to the small-angle scatterings. > > For a number of reasons that go beyond my knowledge of the system, > physicists prefer a different explanation for what is happening in this > second case. Instead of an account in which the momentum is transferred > from the incident neutron to the outgoing proton, this second case is > explained by the neutron becoming a proton, and the proton becoming a > neutron, and the neutron-now-proton continuing on its way at a small > deflection angle. In this account there is a virtual pion that is > exchanged between the neutron and the proton, which causes the proton to > become a neutron and vice versa. In one direction the exchange involves a > positively charged pion, and in another direction it involves a negatively > charged pion. Because these pions have ~ 134 MeV mass, their range is > quite short, and beyond this range, the effect becomes negligible. > > What I wonder is what the distribution of the range of this interaction > looks like going out one or two standard deviations, sort of like the > high-energy tail in the Boltzmann distribution. Perhaps over the duration > of a low-energy np scattering, the virtual pion can only make it out to > several femtometers before the uncertainty principle makes it improbable. > But if there's a long-range tail to this kind of interaction, which occurs > with less probability, longer range interactions might be able to occur at > significant probabilities when considered over longer periods of time. > > If so, we would not have a ~ 1GeV rest-mass neutron traveling from a 7Li > to a nickel nucleus, but instead a ~ 134 MeV virtual pion being exchanged > between a neutron in the 7Li and a proton in the nickel nucleus, causing > them to change into one another. > > Eric > >
