SUSY--QCD corrections to scalar quark decays into charginos and neutralinos

Abstract

We calculate the supersymmetric QCD corrections in order ${\alpha }_s$ to the decays ${\text{squark}}_i\to q^{\prime }{\text{chargino}}_j$ (i,j = 1,2) and ${\text{squark}}_i\to q{\text{neutralino}}_k$ (k = 1,...4) within the Minimal Supersymmetric Standard Model. In particular we consider the decays of squarks of the third generation, ${\text{stop}}_i$ and ${\text{sbottom}}_i$ (i = 1,2), where the left--right mixing must be taken into account. The corrections turn out to be of about 10\%, except for higgsino--like charginos or neutralinos, where they can go up to 40\%.

Comments: 15 pages (including 5 figures). Tiny corrections in the text are made. An acknowledgement is added. Figures 2 - 5 are replaced by new ones (change in one curve in each figure). To be published in Phys. Lett. B