Resonances and unitarity in weak boson scattering at the LHC

Abstract

A crucial test of the Standard Model is the measurement of electroweak gauge-boson scattering. In this paper, we describe a generic parameterization aimed at a realistic simulation of weak-boson scattering at the LHC. The parameterization implements resonances of all possible spin and isospin combinations, properly matched to the low-energy effective (chiral) Lagrangian, includes leading higher-order effects and contains a minimal unitarization scheme. We implement the parameterization in the Monte-Carlo event generator WHIZARD and present results for complete partonic cross-section integration and event generation. We provide a comparison with the effective W approximation that previously has been used for most W W scattering studies at hadron colliders.

Study of the Electroweak Symmetry Breaking Sector for the LHC

“…[150] in the context of the Higgsless ECL model 2 , is the tensor-isotensor channel. Here again K 22 = E 22 = 0, so that the amplitude in perturbation theory is real for physical energy.…”

“…For instance, in appendix D.4, we have compared the elastic NLO partial waves with the ECL (Higgs-less) model of ref. [150], when a = b = 0. And the work of Espriu et al [158] is also a good check of the unitarized parameter space of the a 4 and a 5 NLO coefficients (see fig.…”

“…In particular, we will quote ref. [150] since, although they worked in the Higgsless ECL model, they have computed the real part of the NLO partial waves (including the tensor-isotensor channel IJ = 22), and their results can be used to check our elastic WBGBs partial waves of eqs. 3.136 to 3.140, taking a = b = 0 in our expressions.…”

“…Furthermore, ref. [150] (and its extension [175]) are particularly encouraging since they are interested in the implementation of strongly interacting theories into their own MonteCarlo program, WHIZARD [188,189].…”

“…[150] has been extended (see ref. [175] for example), but apparently a non-linear chiral Lagrangian of the form of eq.…”