It has been pointed out recently by Chanowitz that the $Z \to b\bar{ b}$ decay asymmetry poses a problem for the standard model whether it is genuine or not [Chanowitz:2001bv]. If this conflict is interpreted as new physics in the b-quark couplings, it suggests a rather large right handed coupling of the b-quark to the Z-boson. We show that it is possible to accommodate this result in left-right models that single out the third generation.
Categories: hep-ph