Density maps for a simulation with a very narrow initial accretion zone. Panel a shows the initial setup (t = 0), and panel b corresponds to t = 20 Pluto time units, i.e., 2.4 stellar rotations. The velocity vectors are shown as black arrows, and the magnetic field lines are represented by the solid white lines. The distances on the vertical (z) and horizontal (ϖ) axis are represented in astronomical units.