How frequently do accelerating electrons emit photons?
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Electron has electric charge it is coupled to the electromagnetic field, and is able to produce excitations in this field which we can call photons. This is literally what it means to have electric charge, so there is no need for a 'mechanism' beyond that. The electron also has weak force charge (isospin), but no strong force charge, so right away we can tell that it cannot directly emit gluons simply because it is not coupled to this field (By the way, don't ask me why an electron has some kinds of charge and not others).
From this, the possible emission channels for an electron are those of the electromagnetic and weak forces: photons, and W and Z bosons. However, W bosons can be ruled out immediately: they have electric charge, so if the electron gave them off it would violate conservation of electric charge. But photons and Z bosons are both neutral, so those are okay.
What else is forbidden? Well, an electron that is at rest cannot give anything off, because that would be creating energy. But the principle of Lorentz invariance tells us that if an electron at rest cannot emit anything, then it also cannot emit anything when it is moving at a constant velocity, because one can always choose a reference frame moving at a different (constant) velocity without changing an observable like whether something was emitted.
Nothing so far has forbidden an electron that is accelerating from emitting a photon or a Z boson, so we should expect that both of these can happen. However, because a Z boson is quite heavy, to emit these without violating energy conservation the electron must be accelerating to a degree that is only possible in a particle accelerator (or similar natural process). Photons can be as low energy as you like since they are massless, so at the energy scales we are used to only emission of photons is possible.
From this, the possible emission channels for an electron are those of the electromagnetic and weak forces: photons, and W and Z bosons. However, W bosons can be ruled out immediately: they have electric charge, so if the electron gave them off it would violate conservation of electric charge. But photons and Z bosons are both neutral, so those are okay.
What else is forbidden? Well, an electron that is at rest cannot give anything off, because that would be creating energy. But the principle of Lorentz invariance tells us that if an electron at rest cannot emit anything, then it also cannot emit anything when it is moving at a constant velocity, because one can always choose a reference frame moving at a different (constant) velocity without changing an observable like whether something was emitted.
Nothing so far has forbidden an electron that is accelerating from emitting a photon or a Z boson, so we should expect that both of these can happen. However, because a Z boson is quite heavy, to emit these without violating energy conservation the electron must be accelerating to a degree that is only possible in a particle accelerator (or similar natural process). Photons can be as low energy as you like since they are massless, so at the energy scales we are used to only emission of photons is possible.
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Hey !
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There are many different ways to produce photons, but all of them use the same mechanism inside an atom to do it.
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Thanks !
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