Speaker
Description
The threshold scan at future lepton colliders is the most precise
known method to determine the top quark mass (well below 100 MeV), a
fundamental parameter of the Standard Model that co-determines the
stability properties of the electroweak vacuum. We present a new method to
match the continuum next-to-leading order QCD corrections with the
next-to-leading logarithmic resummation of the Coulomb singularities of the
quasi-toponium bound state at threshold where fixed-order perturbation
theory is invalid. This matching is performed at the level of the fully
exclusive WbWb final state. It allows to study all kinds of differential
distributions at or close to threshold. The top mass dependence of these
distributions opens up new possibilities for the top mass determination
that might be competitive with the inclusive threshold scan.
