2009/09/07 by R. Martinez, Ricardo del Olmo Martínez, F. Ochoa
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.80.075020
published as Phys.Rev.D80:075020,2009
arxiv created 2009/09/07 · openalex publication_date 2009/10/30 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
One-loop corrections to the Z^\ensuremath' decay width are derived and analyzed in the framework of the general form of the 3-3-1 models. We identify two important sources of corrections: oblique corrections associated to the Z^\ensuremath' propagator through vacuum polarizations induced by virtual particle-antiparticle pairs of new heavy quarks J, and vertex corrections to the Z^\ensuremath'qq vertex through virtual exchange of new K^Q1,2 gauge bosons. Fixing a specific renormalization scheme, we obtain dominant oblique corrections that exhibit a quadratic dependence on the J quark mass, which are absorbed into two oblique parameters: a global parameter \ensuremathρf^\ensuremath' which modify the Z^\ensuremath' decay width, and a parameter \ensuremathκf^\ensuremath' that define effective Z^\ensuremath' couplings. Numerical results in an specific 3-3-1 model gives a strong contribution of the oblique corrections from about 1.3% in the d(s) quark channel to 10.5% in the neutrino channel, for mJ=2 TeV. The vertex corrections contribute to the oblique corrections up to 1.4% for the same channel and mJ value. For pp collisions at the CERN LHC collider, we find that the corrections significantly modify the shape of the cross section distributions for e+e^\ensuremath- and tt final states, where the distributions including the radiative corrections increases up to 1.23 times the tree-level distribution for the dielectron events and to 1.07 for the top events when mJ=3 TeV.