ICHEP2012

Dynamical Origin of the Correlation between the Top Quark Production Asymmetries AFBt and AFBℓ

Not scheduled

17m

Melbourne Convention and Exhibition Centre

Parallel Sessions Track 4 - Top Quark Physics

Speaker

Dr Edmond Berger (Argonne National Laboratory (US))

Description

A larger than expected forward-backward asymmetry in rapidity is observed in top quark pairs produced in proton-antiproton collisions at the Tevatron. The asymmetry is seen in both the top quark rapidity distribution $A_{FB}^t$ and in the distribution of charged leptons $A_{FB}^{\ell }$ from top quark decay. We explore the kinematic and dynamic aspects of the tight relationship of the two observables arising from the spin correlation between the charged lepton and the top quark with different polarization states. We also consider two benchmark new physics models, an axigluon model and a flavor-changing $W^{\prime }$ model. These models could explain the values of both $A_{FB}^t$ and $A_{FB}^{\ell }$. We emphasize the value of both measurements, and we conclude that a model which produces more right-handed than left-handed top quarks is favored by the present data. (The presentation would be based on the material in Phys Rev Lett. 108, 072002 (2012) [arXiv:1201.1790] and subsequent work.)