Field lines close to the stagnation surface. The lines are over-collimated at the beginning, which is in agreement with the high value of the toroidal magnetic field. All the distances are on a scale of a thousand Schwarzschild radii (1000 r_s). Blue lines refer to the flow before the critical point, whereas the red ones refer to after it has crossed the critical point. $\varpi =\sqrt{R^2+l^2}sin\theta$ and $z=\sqrt{R^2+l^2}cos\theta$.