Ref Arxiv: hep-ph/0003143
DOI: 10.1103/PhysRevD.62.073013
Ref. & Cit.: NASA ADS
51 citations
Résumé:

We examine the standard and the new physics (NP) contributions to the ZZZ, ZZγ, and Zγγ neutral gauge couplings. At the one-loop level, if we assume that there is no CP violation contained in NP beyond the standard model (SM) one, we find that only CP conserving neutral gauge couplings are generated, either from the standard quarks and leptons, or from possible new physics fermions. Bosonic one-loop diagrams never contribute to these couplings, while the aforementioned fermionic contributions satisfy hZ3~=-fγ5, hZ4=hγ4=0. We also study examples of two-loop NP effects that could generate nonvanishing hγ,Z4 couplings. We compare quantitative estimates from SM, minimal supersymmetric standard model (MSSM), and some specific examples of NP contributions, and we discuss their observability at future colliders.