This is a dangerous formulation that can easily be interpreted in the wrong way, for that reason i say your answer is wrong.
The beta decay really announced the advent of QFT. In the beginning some scientists thought that the electron really came out of the nucleus, ofcourse this is wrong. What happens is this : the electron is created "out of nothing". This means that the energy involved in the beta decay is used to create this electron out of the vacuum. This kind of process is only possible in QFT and that is why beta decay was one of the first major breakthroughs of QFT.
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(RA) Of course the electron/positron comes out of the nucleus -- where else can it come from?
Yes, beta decay's specific mechanism is nucleon -> nucleon' + e/p + neutrino. Let's focus on standard beta deay in which a nucleus emits an electron, the neutron number goes down by one, the proton number goes up by one. So, indeed, beta decay can and does create an ion -- an ion really does not care where it came from -- the lifetime of which can vary considerably, dependent as it is on the environment of the nucleus. There is, in fact, a chance that the escaping electron could be captured -- probably the probability for this is small, and gets smaller the higher the electron's energy is.
A little history. Prior to his ground breaking work on beta decay, Fermi played a major role in developing QED, along with Dirac, Pauli, and Heisenberg. (And remember that Chadwick did not find the neutron until 1932, which meant no successful theory was possible for nucleii until 1932.) Fermi's 4-point interaction for beta decay was, in fact, inspired by QED -- for practical purposes, Fermi's approach was based on current-current interactions, and was first published in 1933. So Fermi's beta decay theory was at best a second triumph of field theory. But make no mistake about it, QED was the first field theory triumph -- all other interacting field theories are formally based on QED.
Again, the electron and neutrino come out of the decaying nucleus. First of all, the Born Approx works nicely for nuclear beta decay. This puts two things into play
1. The Pauli Principal says that all neutrons are at play. If the energetics are favorable, then a neutron will decay-- which one? Who knows.
2. And, when computing the Born Approx decay rate, the relevant integral is non-zero only within the nucleus, and appropriate antisymmetric wave functions must be used for initial and final states.
The structure of the 4-point interation, generically (N(x) v(x) P(x) e(x)+adjoint, where N is a neutron field, P a proton field, v a neutrino field, and e an electron field. I've not worried about adjoints, nor about the various gamma matrices involved. This pretty clearly says the leptons are not created from the vacuum -- conservation laws more-or-less preclude such a phenomena. Fermi's idea was the neutron transformed into proton, electron, neutrino. He's been more than vindicated, as in nuclear beta decay, the intermediate vector bosons basically contribute a 1/M*M, with M the vector boson mass, as the momentum/energy transfer is very small compared to M) This interaction allows the computation of the probability that a beta decay will occur at any place inside the nucleus, that is that the electron and neutrino do indeed emerge from the nucleus because they are formed inside the nucleus. The matrix elements are generally non-zero. but the decay can occur only if the energetics are favorable-- the neutron decays because the neutron mass is greater than the combined rest masses of the electron and proton. For nucleii, the initial nucleii must have a mass greater than the final nucleii and electron.
Regards,
Reilly Atkinson
