Probing top anomalous couplings at the LHC with trilepton signatures in the single top mode

Abstract

We investigate trilepton final states to probe top anomalous couplings at the Large Hadron Collider. We focus on events originating from the associated production of a single top quark with a Z-boson, a channel sensitive to several flavor-changing neutral interactions of top and up/charm quarks. In particular, we explore a way to access simultaneously their anomalous couplings to Z-bosons and gluons and derive the discovery potential of trilepton final states to such interactions with 20 fb-1 of 8 TeV collisions. We show that effective coupling strengths of O(0.1-1) TeV-1 can be reached. Equivalently, branching fractions of top quarks into lighter quarks and gluons or Z-bosons can be constrained to be below O(0.1-1)%.