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Extra Generations, Discrepancies of Electroweak Precision Data and Mass of the Higgs

V. A. Novikov
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Abstract

The latest electroweak precision data are analyzed assuming the existence of the fourth generation of leptons ($N, E$) and quarks ($U, D$), which are not mixed with the known three generations. If all four new particles are heavier than $Z$ boson, quality of the fit for the one new generation is as good as for the Standard Model. In the case of neutral leptons with masses around 50 GeV (``partially heavy extra generations'') the minimum of $χ^2$ is between one and two extra generations. The predicted value of the higgs mass $m_H$ in the presence of the fourth generation can be made rather large. The quality of fits drastically improves when the data on b- and c-quark asymmetries and new NuTeV data on deep inelastic scattering are ignored.

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V. A. Novikov. 2002-05-29. Extra Generations, Discrepancies of Electroweak Precision Data and Mass of the Higgs. https://arxiv.org/abs/hep-ph/0205320

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