How frequently do accelerating electrons emit photons?
Answers
By definition, because an 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.