Non-Fermi-Liquid Behavior in Ce(Ru$_{0.5}$Rh$_{0.5}$)$_2$Si$_2$

We study the temperature and field dependence of the magnetic and transport properties of the non-Fermi-liquid compound Ce(Ru$_{1-x}$Rh$_x$)$_2$Si$_2$ at $x=0.5$. For fields $\lesssim $0.1T the experimental results show signatures of the presence of Kondo-disorder, expected to be large at this concentration. For larger fields, however, the physics is controlled by the coupling of the conduction electrons to critical spin-fluctuations. The temperature dependence of the susceptibility as well as the scaling properties of the magnetoresistance are in very good agreement with the predictions of recent dynamical mean-field theories of Kondo alloys close to a spin-glass quantum critical point.