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Loop Effects of Exotic Leptons on Vector-Boson Pair Production at e^+e^- Colliders

K. -P. O. Diener·B. A. Kniehl·A. Pilaftsis
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Abstract

We study quantum effects of exotic heavy leptons on the production of two vector bosons in e^+e^- annihilation. We present closed analytic expressions for vector-boson self-couplings and differential cross sections, within the framework of two favourable new-physics scenarios: (i) the fourth-generation Majorana-neutrino model and (ii) an E_6-inspired model with sequential mirror isodoublets. We constrain these models by requiring that their contributions to the oblique electroweak parameters be compatible with a recent global fit to high-precision data. We then systematically analyze the loop-induced deviations in the LEP2 cross section of e^+e^- -> W^+W^- predicted by the models thus confined.

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K. -P. O. Diener, B. A. Kniehl, A. Pilaftsis. 1997-09-16. Loop Effects of Exotic Leptons on Vector-Boson Pair Production at e^+e^- Colliders. https://doi.org/10.1103/physrevd.57.2771

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