Robust determination of the scalar boson couplings

TL;DR

This paper performs a comprehensive global analysis of Higgs-like particle data using an effective field theory approach, constraining scalar couplings and electroweak gauge interactions with updated experimental results.

Contribution

It introduces a dimension-six operator framework for analyzing Higgs couplings, enabling simultaneous constraints on multiple parameters with the latest data.

Findings

Strong constraints on scalar couplings to gluons and gauge bosons.

Simultaneous determination of Higgs couplings to fermions.

Enhanced bounds on electroweak triple gauge boson couplings.

Abstract

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 new versions of the manuscript.