## Neutron to Proton

 Quote by Atakor Hello daschaich, where does that $$\gamma$$ come from ???
That's a photon, which can be radiated by any electrically charged particle -- the proton, electron, intermediate W boson, probably even the individual quarks in the initial-state neutron. The paper jal posted discussed experiments trying to determine how likely it is for such a photon (with an energy of at least 35 keV) to be emitted during $$\beta$$ decay.

Blog Entries: 30
 In our case, when proton kinetic energy was 25 keV, the final velocity was 0.006 c, and its average velocity along the trajectory was 0.003 с. On Fig. 6, which shows the spectrum of the electron-proton coincidences, the peak of these coincidences is located in the 120th channel, which corresponds to proton delay of 500 ns on average or the distance between the point of decay and the proton detector in 40-50 cm. The estimate obtained is quite good and coincides with the real distance between the proton detector and the axis of neutron beam in our equipment with precision of ten-twenty per cent.
In the paper, they were able to position the detectors so that they were able to detect the proton, the photon, then the electron.
My understanding is that they captured some free neutron in a “cold thermos bottle”. They did some calculation to arrive at neutrons at rest, and measured “decayed/changed” to a proton. By measuring the time of flight they were able to determine that an electron and a neutrino, were formed from the “Fermi sea” (to make sure that there is conservation of energy).
In order for the electron to emit a photon it has to go from a “bigger orbit” to a “smaller orbit” around the proton.
The change in the orbit determines the “size” of the photon recorded on the detector.
Then, the electron was “pulled out” of orbit and into another detector.
Yes? No? … Okay! …. What really happened?
 Blog Entries: 30 I want to make a quote that explains, for most people, what scientists have concluded happens when a free neutron changes to a proton. For me, it raises more questions and that’s why I searching for experimental evidence. ------- Hydrogen: The Essential Element John S. Rigden 2002 “p. 167 A static charge, like the electron, takes a new life in QED. An electron has a n electromagnetic field consisting of quantized photons. Thus, the electron is surrounded by a cloud of photons. This cloud of photons surrounding an electron effectively reproduces the 1/r^2 character of its measured electric field given by Coulomb’s law. The electron can interact with its own electromagnetic field; that is, with photons in the cloud surrounding it. This interaction alters the behavior the electron would have in the absence of these interactions. To give a complete theoretical account of the electron interaction with its own field, corrections must be made by QED; in fact by a new relativistic theory of QED. In the summer of 1947 Julian Schwinger … did with spectacular success during the next six months. There is another consequence of the photon cloud around an electron. In this cloud of photons, the creation and annihilation of particles occur. It is these virtual particles, pairs of positive and negative particles, that lead to the polarization of the empty space surrounding the electron. Thus, the charge of the electron is partially screened from an outside viewer and, from a distance, appears slightly different from what it really is. Incidentally, quantum electrodynamics transcends the electron. In other words, the idea of QED go beyond the electron. For example the concept of a basic interaction being mediated by an exchange of particles has been extended to both the weak and strong interactions with mediated particles experimentally identified.” ---------- So my original questions, “Why does the change need to include the intermediate step of the heavy W boson? Where did all the W boson mass come from and where did it go?” has been answered superficially. Re-phrasing … QED … says so and it is assumed that it is the same for a free neutron. but ... is it?