A “composite” scalar–vector system at the LHC

In the framework of a strong dynamics for Electro-Weak Symmetry Breaking (EWSB), both vector and scalar degrees of freedom have been studied in the literature within an effective Lagrangian approach. Here we consider the case in which both a scalar, h, and a vector, V   – respectively an iso-singlet and an iso-triplet under a custodial SU(2)SU(2) – are relevant with a mass below the cut-off Λ≈4πvΛ≈4πv. We study the amplitudes for the processes WLWL→WLWL,hh,VLVL,VLhWLWL→WLWL,hh,VLVL,VLh. Requiring unitarity for the elastic channel WLWL→WLWLWLWL→WLWL we can reduce the parameter space to two free parameters for given masses of the heavy vector and the scalar. We study the numerical total cross sections for the associated productions pp→Vhjjpp→Vhjj by Vector Boson Fusion (VBF) and pp→Vhpp→Vh by Drell–Yan (DY) annihilation as functions of these free parameters. The expected rates of same-sign di-lepton and tri-lepton events from the decay of the Vh final state are also given.