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arXiv · hep-ph/9612314

Z' interference effects from TRISTAN to LEP2

P. Osland·A. A. Pankov
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Abstract

We discuss the potential of present e^+e^- colliders to probe for a heavy Z^' boson via its interference effects, in a model-independent framework. The leptonic channel is unambiguous, and thus favourable over the hadronic ones. The effect on the leptonic cross section $σ_{μμ}$, induced by a heavy Z^' with arbitrary couplings, is uniquely determined at LEP2 energies. It results in a negative deviation from the standard model prediction, due to destructive $γ-Z'$ and Z-Z' interferences. At TRISTAN energies the former dominates and is given by the vector coupling of the Z^'. Around the Z peak, the Z-Z' interference dominates and depends on the axial-vector coupling. The forward-backward asymmetry is complementary to $σ_{μμ}$ in the Z^' search. Comparison of the e^+e^- potentials indicates that already after one year of operation, LEP2 will achieve a sensitivity to Z^' that exceeds the current one at TRISTAN.

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P. Osland, A. A. Pankov. 1996-12-10. Z' interference effects from TRISTAN to LEP2. https://doi.org/10.1016/s0370-2693(97)00488-7

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