Single-photon events in e(+)e(-) collisions - art. no. 013007

We provide a detailed investigation of single-photon production processes i n e(+)e(-) collisions with missing momenta carried by neutrinos or neutrali nos. The transition amplitudes for both processes can be organized into a g eneric simplified, factorized form; each neutral V+/-A vector current of mi ssing energy carriers is factorized out and all the characteristics of the reaction are solely included in the electron vector current. Firstly, we ap ply the generic form to give a unified description of single-photon product ion with a Dirac-type or Majorana-type neutrino pair and to confirm their i dentical characteristics as suggested by the so-called practical Dirac-Majo rana confusion theorem. Secondly, we show that the generic amplitude form i s maintained with the anomalous P- and C-invariant WW gamma couplings in th e neutrino-associated process and it enables us to easily understand the la rge contributions of the anomalous WW gamma couplings at higher energies an d, in particular, at points away from the Z-resonance peak. Finally, the ne utralino-associated process, which receives modifications in both the left- handed and right-handed electron currents due to the exchanges of the left- handed and right-handed selectrons, can be differentiated from the neutrino -associated ones through the left-right asymmetries and/or the circular pol arization of the outgoing photon. [S0556-2821(99)07113-1].