Comparisons of Theory Predictions for the ttbar Process with Data from pp Collisions at sqrt(s)= 8 TeV

Studies are presented comparing $t \bar{t}$ differential distribution data collected with the CMS detector at $\sqrt{s}=8$ TeV to state-of-the-art theoretical predictions. The predictions are accurate to next-to-leading order quantum chromodynamics and interfaced with the PYTHIA 8 and HERWIG++ event generators. The predictions of these simulation tools and a next-to-next-to-leading order calculation are compared to unfolded data distributions. All deviations of the theory predictions from the data remain inside the envelope considered for factorization and renormalization scale variations.