P t ) planes in the semileptonic rest frame decay of a polarized top quark : An O ( α s ) effect

Azimuthal correlation between the (p ℓ , p X b) and (p ℓ , P t) planes in the semileptonic rest frame decay of a polarized top quark: An O(α s) effect Abstract The azimuthal correlation between the planes formed by the vectors (p ℓ , p X b) and (p ℓ , P t) in the semileptonic rest frame decay of a polarized top quark t(↑) → X b + l + + ν ℓ belongs to a class of polarization observables involving the top quark which vanish at the Born term level in the standard model. We determine the next–to–leading order QCD corrections to the afore-mentioned azimuthal correlation and compare the result to the corresponding contribution of a non–standard–model right–chiral quark current.