To observe nonlinearity in the stopping power of a nonideal plasma for heavy ions, we are planning a beam-plasma interaction experiment using 10-100 keV/u projectiles. For the interaction experiment, a nonideal hydrogen plasma target was developed by means of a shock technique. Time-resolved spectroscopic measurements determined the temporal evolution of the electron density and temperature of the shock plasma. These data revealed that the structure behind the shock front has an appropriate spatial and temporal distribution to be used as a target. We also evaluated the temporal evolution of the Coulomb coupling constant and the degree of ionization at a fixed position where the projectiles are injected. We discuss the feasibility of the nonlinear stopping experiment by evaluating the beam-plasma coupling constant expected from the measured plasma parameters.