Periods of the shock oscillations (P_osc, upper panel), maximum extension of the post-shock zone (l_max, middle panel) and the emission-measure-weighted temperature (T_ps, bottom panel) of all the cases investigated. The labels on the x-axis of the bottom panel indicate the densities of accretion stream. Different symbols indicate different velocities: u_acc = 200 (circle), 400 (squares), and 600 (triangles) km s^-1. Different colors indicate different metal abundances: ζ = 0.2 (black), 1.0 (red) and 5.0 (green). Note that data points have been spread over each density value to prevent overlapping of the symbols.