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تسجيل مستخدم جديدInvestigations of electroweak symmetry breaking mechanism for Higgs boson decays into four fermions
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Models with extended Higgs boson sectors are of prime importance for investigating the mechanism of electroweak symmetry breaking for Higgs decays into four fermions and for Higgs-production in association with a vector bosons. In the framework of the Two-Higgs-Doublet Model using two scenarios obtained from the experimental measurements we presented next-to-leading-order results on the four-fermion decays of light CP-even Higgs boson, $h rightarrow 4f$. With the help of Monte Carlo program Prophecy 4f 3.0, we calculated the values $Gamma= Gamma_{EW} /left(Gamma_{EW}+Gamma_{SM}right)$ and $Gamma= Gamma_{EW+QCD} /left(Gamma_{EW+QCD}+Gamma_{SM}right)$ for Higgs boson decay channels $ H rightarrow u_{mu} overline{mu} e overline{ u_e}$, $mu overline{mu} e overline{e}$, $e overline{e} e overline{e}$. We didnt find significant difference when accounting QCD corrections to EW processes in the decay modes of Higgs boson. Using computer programs Pythia 8.2 and FeynHiggs we calculated the following values: $sigma(VBH)BR(Hrightarrow ZZ)$ and $sigma(VBF)BR(H rightarrow WW)$ for VBF production processes, $sigma(ggH)BR(H rightarrow WW)$ and $sigma(ggH)BR(H rightarrow ZZ)$ for gluon fusion production process at 13 and 14 TeV and found good agreement with experimental data.
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