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Fermion Virtual Effects in $e^+ e^- -> W^+ W^-$ Cross Section

A. Culatti·G. Degrassi·F. Feruglio·A. Masiero·S. Rigolin·L. Silvestrini·A. Vicini
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Abstract

We analyse the contribution of new heavy virtual fermions to the $e^+e^- \rightarrow W^+W^-$ cross section. We find that there exists a relevant interplay between trilinear and bilinear oblique corrections. The result strongly depends on the chiral or vector--like nature of the new fermions. As for the chiral case we consider sequential fermions: one obtains substantial deviation from the Standard model prediction, making the effect possibly detectable at $\sqrt{s}=500$ or $1000$ GeV linear colliders. As an example for the vector--like case we take a SUSY extension with heavy charginos and neutralinos: due to cancellation, the final effect turns out to be negligible.

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A. Culatti, G. Degrassi, F. Feruglio, A. Masiero, S. Rigolin, L. Silvestrini, A. Vicini. 1996-05-28. Fermion Virtual Effects in $e^+ e^- -> W^+ W^-$ Cross Section. https://arxiv.org/abs/hep-ph/9605415

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