Beautiful mirrors for a pNGB Higgs

We consider one of the most significant deviations from the standard model: the forward-backward asymmetry of the b-quark measured at leptonic colliders. we investigate the possibility to solve this discrepancy by introducing new physics at the tev scale. we focus on models where the higgs is a pseudo nambu-goldstone boson of a new strongly coupled sector with a global so(5) symmetry broken spontaneously to so(4). besides the usual top partners, we introduce bottom partners in the representations 16 and 4 of so(5) and show that they can improve significantly the fit by correcting the $$ zboverline{b} $$ couplings. we also estimate the corrections to the couplings at one-loop and obtain that the tree-level ones dominate and can give a reliable estimation. we find that the large shift required for $$ z{b}_r{overline{b}}_r $$ leads to light custodians associated to the b-quark, similar to the top partners, as well as a rich phenomenology involving neutral interactions in the bottom-sector.