Journal of High Energy Physics

, 2015:125 | Cite as

8D likelihood effective Higgs couplings extraction framework in h → 4

  • Yi Chen
  • Emanuele Di Marco
  • Joe Lykken
  • Maria Spiropulu
  • Roberto Vega-MoralesEmail author
  • Si Xie
Open Access
Regular Article - Experimental Physics


We present an overview of a comprehensive analysis framework aimed at performing direct extraction of all possible effective Higgs couplings to neutral electroweak gauge bosons in the decay to electrons and muons, the so called ‘golden channel’. Our framework is based primarily on a maximum likelihood method constructed from analytic expressions of the fully differential cross sections for h → 4 and for the dominant irreducible \( q\overline{q} \) → 4 background, where 4 = 2e2μ, 4e, 4μ. Detector effects are included by an explicit convolution of these analytic expressions with the appropriate transfer function over all center of mass variables. Utilizing the full set of observables, we construct an unbinned detector-level likelihood which is continuous in the effective couplings. We consider possible ZZ, , and γγ couplings simultaneously, allowing for general CP odd/even admixtures. A broad overview is given of how the convolution is performed and we discuss the principles and theoretical basis of the framework. This framework can be used in a variety of ways to study Higgs couplings in the golden channel using data obtained at the LHC and other future colliders.


Hadron-Hadron Scattering Higgs physics 


Open Access

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Copyright information

© The Author(s) 2015

Authors and Affiliations

  • Yi Chen
    • 1
  • Emanuele Di Marco
    • 2
  • Joe Lykken
    • 2
  • Maria Spiropulu
    • 1
  • Roberto Vega-Morales
    • 2
    • 3
    • 4
    Email author
  • Si Xie
    • 1
  1. 1.Lauritsen Laboratory of PhysicsCalifornia Institute of TechnologyPasadenaU.S.A.
  2. 2.Theoretical Physics Department, FermilabBataviaU.S.A.
  3. 3.Laboratoire de Physique Théorique d’Orsay, UMR8627-CNRSOrsay CedexFrance
  4. 4.Department of Physics and AstronomyNorthwestern UniversityEvanstonU.S.A.

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