We review a Soft Collinear Effective Theory approach to the study of factorization and resummation of QCD effects in top-quark pair production. In particular, we consider differential cross sections such as the top-quark pair invariant mass distribution and the top-quark transverse momentum and rapidity distributions. Furthermore, we focus our attention on the large invariant mass and large transverse momentum kinematic regions, characteristic of boosted top quarks. We discuss the factorization of the differential cross section in the double soft gluon emission and small top-quark mass limit, both in Pair Invariant Mass (PIM) and One Particle Inclusive (1PI) kinematics. The factorization formulas can be employed in order to implement the simultaneous resummation of soft emission and small mass effects up to next-to-next-to-leading logarithmic accuracy. The results are also used to construct improved next-to-next-to-leading order approximations for the differential cross sections.
تحميل البحث