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Robust determination of the scalar boson couplings

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 نشر من قبل Juan Gonzalez-Fraile
 تاريخ النشر 2013
  مجال البحث
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We study the indirect effects of new physics on the phenomenology of the Higgs-like particle. Assuming that the recently observed state belongs to a light electroweak doublet scalar and that the SU(2)_L x U(1)_Y symmetry is linearly realized, we parametrize these effects in terms of an effective Lagrangian at the electroweak scale. We choose the dimension--six operator basis which allows us to make better use of all the available data to constrain the coefficients of the dimension-six operators. We perform a global 6--parameter fit which allows simultaneous determination of the standard model scalar couplings to gluons, electroweak gauge bosons, bottom quarks, and tau leptons. The results are based on the data released at Moriond 2013. Moreover, our formalism leads to strong constraints on the electroweak triple gauge boson couplings. Note added: The analysis has been updated with a NEW GLOBAL 6-PARAMETER FIT with all the public data available after Moriond 2013. Updates of this analysis are provided at the website http://hep.if.usp.br/Higgs, as well as n



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