The oblique S parameter in higgsless electroweak models

Abstract

We present a one-loop calculation of the oblique S parameter within Higgsless models of electroweak symmetry breaking. We have used a general effective Lagrangian with at most two derivatives, implementing the chiral symmetry breaking SU(2)_L x SU(2)_R -> SU(2)_{L+R} with Goldstones, gauge bosons and one multiplet of vector and axial-vector resonances. The estimation is based on the short-distance constraints and the dispersive approach proposed by Peskin and Takeuchi.Comment: 5 pages, 2 figures. Talk given at QCD@work 2012, International Workshop on Quantum Chromodynamics: Theory and Experiment, 18-21th June (2012), Lecce (Italy