Infrared fixed point of the top Yukawa coupling in split supersymmetry

The severe constraints imposed on the parameter space of the minimal split supersymmetry model by the infrared fixed point solution of the top Yukawa coupling $Y_t$ are studied in detail together with the lower bound on the lightest Higgs mass established by LEP. The sensitive dependence of the higgsino mass parameter $\mu$ and gaugino coupling strengths ${\tilde g}_{u,d}$, ${\tilde g}^\prime_{u,d}$ on the value of $Y_t$ in the vicinity of the Landau pole is a remarkable consequence. Several other interesting features are highlighted.