Light stop decays into Wb(χ)over-tilde10 near the kinematic threshold

We investigate the decays of the light stop in scenarios with the lightest neutralino (chi) over tilde (0)(1) being the lightest supersymmetric particle, including flavour-violating (FV) effects. We analyse the region where the three-body decay (t) over tilde (1) -> Wb (chi) over tilde (0)(1) is kinematically allowed and provide a proper description of the transition region between the three-body decay and the four-body decay (t) over tilde (1) -> (chi) over tilde (0)(1)bf (f) over bar'. The improved treatment has been implemented in the Fortran package SUSY-HIT and is used for the analysis of this region. A scan over the parameter range including all relevant experimental constraints reveals that the FV two-body decay into charm and (chi) over tilde (0)(1) can be as important as the three-, respectively, four-body decays if not dominant and therefore should be taken into account in order to complete the experimental searches for the light stop. (C) 2015 The Authors. Published by Elsevier B.V.