Resonant production of fermions in an axial background - art. no. 083510

We consider the resonant production of fermions from an oscillating axial b ackground. The classical evolution of the axial field is given by that of a massive pseudovector field, as suggested by the renormalizability of the t heory. We look upon both the massive and the massless fermion production fr om a perturbative point of view. We obtain the corresponding spectrum and a ngular distributions for the different spins or helicities in the particula r case of a spatial-like axial held. We also extend our study to the nonper turbative regime in the massless case and compare the results with the pert urbative ones. [S0556-2821(99)04308-8].