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arXiv · 1405.1498

Constraining Top partner and Naturalness at the LHC and TLEP

Chengcheng Han·Archil Kobakhidze·Ning Liu·Lei Wu·Bingfang Yang
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Abstract

We investigate indirect constraints on the top partner within the minimal fermionic top partner model. By performing a global fit of the latest Higgs data, $B_s \to μ^+μ^-$ measurements and the electroweak precision observables we find that the top partner with the mass up to 830 GeV is excluded at $2σ$ level. Our bound on the top partner mass is much stronger than the bounds obtained from the direct searches at the LHC. Under the current constraints the fine-tuning measure is less than 9% and the branching ratio of $T \to tZ$ is bounded between 14% and 25%. We also find that precise measurements of Higgs couplings at 240 GeV TLEP will constrain the top partner mass in multi-TeV region.

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Chengcheng Han, Archil Kobakhidze, Ning Liu, Lei Wu, Bingfang Yang. 2014-12-14. Constraining Top partner and Naturalness at the LHC and TLEP. https://doi.org/10.1016/j.nuclphysb.2014.11.021

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