HELICITY-FLIP BREMSSTRAHLUNG - AN EQUIVALENT PARTICLE DESCRIPTION WITH APPLICATIONS

We examine collinear bremsstrahlung accompanied by helicity-flip (i.e. e(L) --> e(R) + gamma, e(L) + gamma) in an equivalent particle approach, using the helicity formalism. It is shown that helicity-flip radiation can be described by a universal function D(hf)(x) = (alpha/2pi)x (x = fractional energy of the photon) analogous to the Weizsacker-Williams distribution describing non-flip bremsstrahlung. Several examples of ''helicity-forbidden'' processes are considered, including e(R)- + p --> gamma + nu(L) + X. e(L)+e(L)- --> mu+mu-gamma, e(L)+e(L)- --> W+W-gamma and e(R)-gamma --> W-nu(e)gamma.