Time sequences of cross sections through the center of the 5 M_⊙ model st35gm04n048 showing the logarithm of density, the logarithm of temperature (restricted to values below T = 20 000 K), the logarithm of opacity (per gram), and the radial velocity with overlaid pseudo-streamlines. The cyan contour line indicates optical depth unity (τ_Ross = 1) for an observer on the right, corresponding to the viewing direction shown in Fig. 10.