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Higgs boson decays to a lepton pair and a $Z$ boson

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 نشر من قبل Zi-Qiang Chen
 تاريخ النشر 2021
  مجال البحث
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The discovery of the Standard Model (SM) Higgs boson at the LHC completed the theory of electroweak and strong interactions. To determine the Higgs bosons intrinsic properties, more measurements on its various decay channels are still necessary. In this paper, we investigate $Hto ellbar{ell}Z$ and $Hto u_ellbar{ u}_ell Z$ (with $ell=e$, $mu$, $tau$) processes at the next-to-leading order electroweak accuracy. The total decay widths, and the differential decay rates with respect to various kinematic variables are obtained. For a typical choice of cut on the invariant mass of lepton pair, we find the branching ratios $mathcal{B}(Hto ellbar{ell}Z)=7.5times 10^{-4}$ (with $ell=e, mu$), $mathcal{B}(Hto tau^-tau^+ Z)=7.3times 10^{-4}$, and $mathcal{B}(Hto u_ellbar{ u}_ell Z)=1.5times 10^{-3}$ (with $ell=e, mu, tau$), which are attainable in the LHC experiments.



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