Forward-backward asymmetry in top quark production from light colored scalars in SO(10) model

The forward-backward asymmetry in top pair production at Tevatron has been reconfirmed by the CDF collaboration with 5.3 fb(-1) of accumulated data. These measurements also report that the asymmetry is the largest in regions of high invariant mass M-t (t) over bar and rapidity difference vertical bar Delta Y vertical bar. We consider light colored sextet scalars appearing in a particular non-supersymmetric SO(10) grand unification model within the (126) over bar scalar representation. These scalar states have masses in the range of 300 GeV - 2 TeV consistent with the requirements of gauge coupling unification and bounds on the proton lifetime. The cross section and the total asymmetry can be simultaneously explained with the contributions of these scalars within 1 sigma. We find that the simultaneous fitting of the cross section, the total asymmetry and the asymmetries in different rapidity and M-t (t) over bar bins gives only a marginal improvement over the SM contribution. We also study various production mechanisms of these colored sextet scalars at the LHC.