Time evolution of plasma temperature A), density B), pressure C) and velocity D) during a complete oscillation of the post-shock zone in the case of an accretion stream with density n_acc = 10¹¹ cm^-3, velocity u_acc = 400 km s^-1 and metal abundance ζ = 1.0. The left (right) panels show the time evolution during the heating (cooling) phase. The dashed lines describe the profiles of the unperturbed initial stellar atmosphere (chromosphere and corona). The shaded areas mark the regions below the thresholds s_abs used to estimate the effects of absorption on the luminosity in the O vii (pale grey) and Ne ix resonance lines (see Sect. 2.4).