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arXiv · 1509.05323

Doublet-singlet model and unitarity

G. Cynolter·J. Kovacs·E. Lendvai
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Abstract

We study the renormalizable singlet-doublet fermionic extension of the Standard Model. In this model, the new vector-like fermions couple to the gauge bosons and to the Higgs via new Yukawa couplings, that allow for nontrivial mixing in the new sector, providing a stable, neutral dark matter candidate. Approximate analytic formulae are given for the mass spectrum around the blind spots, where the dark matter candidate coupling to $h$ or $Z$ vanishes. We calculate the two particle scattering amplitudes in the model, impose the perturbative unitarity constraints and establish bounds on the Yukawa couplings.

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G. Cynolter, J. Kovacs, E. Lendvai. 2015-12-18. Doublet-singlet model and unitarity. https://doi.org/10.1142/s0217732316500139

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