Figure 4

Forces along a field line in the jet. Panel (a) shows the poloidal matter flux density \rho |{\mathbf{v}}_p| as a background overplotted with poloidal magnetic field lines. The vectors show the total force {\mathbf{f}}_{\mathrm{tot}} along a representative field line originating from the disk at r=1.24. Panel (b) plots the angular velocity Ω as the background. The vectors show the sum of the gravitational + centrifugal forces {\mathbf{f}}_{\mathrm{G}+\mathrm{C}} along the representative field line. Panel (c) shows the poloidal current I_p as the background. The vectors show the total magnetic force {\mathbf{f}}_{\mathrm{M}} along the representative field line.