Two-body decays of gluino at full one-loop level in the quark-flavour violating MSSM

Abstract

We study the two-body decays of the gluino at full one-loop level in the Minimal Supersymmetric Standard Model with quark-flavour violation (QFV) in the squark sector. The renormalization is done in the $\overline{\rm DR}$ scheme. The gluon and photon radiations are included by adding the corresponding three-body decay widths. We discuss the dependence of the gluino decay widths on the QFV parameters. The main dependence stems from the $\tilde c_R - \tilde t_R$ mixing in the decays to up-type squarks, and from the $\tilde s_R - \tilde b_R$ mixing in the decays to down-type squarks due to the strong constraints from B-physics on the other quark-flavour mixing parameters. The full one-loop corrections to the gluino decay widths are mostly negative and of the order of about -10\%. The QFV part stays small in the total width but can vary up to -8\% for the decay width into the lightest squark. For the corresponding branching ratio the effect is somehow washed out by at least a factor of two. The electroweak corrections can be as large as 35\% of the SUSY QCD corrections.