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arXiv · hep-ph/9906266

Bounds on Kaluza-Klein excitations of the SM vector bosons from electroweak tests

A. Strumia
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Abstract

Within a minimal extension of the SM in 4+1 dimensions, we study how Kaluza Klein excitations of the SM gauge bosons affect the electroweak precision observables. Asymmetries in Z decays provide the dominant bound on the compactification scale M of the extra dimension. If the higgs is so light that will be discovered at LEP2, we find the following 95% CL bounds: M > 3.5 TeV (if the higgs lives in the extra dimension) and M > 4.3 TeV (if the higgs is confined to our 4 dimensions). In the second case Kaluza Klein modes give "universal"corrections and a good fit of precision data can be obtained with an heavier higgs (up to 500 GeV) and with a smaller M > 3.4 TeV.

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A. Strumia. 1999-09-28. Bounds on Kaluza-Klein excitations of the SM vector bosons from electroweak tests. https://doi.org/10.1016/s0370-2693(99)01102-8

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