Figure 17: Three-dimensional plots of entropy with the magnetic field lines (a) and the streamlines of the matter (b) during the jet propagation at ms and ms after bounce, respectively (for model B12TW1 taken from [268]). The outer edge of the sphere colored by blue represents the radius of  cm. These panels highlight not only the wound-up magnetic field around the rotational axis (a), but also the fallback of the matter from the jet head of the downwards to the equator, making a cocoon-like structure behind the jet (b).