Vertical velocity, v_z distribution in the y−z plane at x = 0 at t = 625, during the straight jet/pre-helical jet phase for simulations with different plasma β highlighting the presence of a straight jet for the runs at higher β. The velocity magnitude is color coded in blue (upflows) and red (downflows). For comparison, the ambient Alfvén speed is ĉ_A = 0.28. The black field lines, all initially closed correspond to the cyan field lines of Fig. 2. Open black field lines for lower β runs indicate the occurrence of relatively more intense reconnection by this stage. The blue and green lines are isocontours of the electric current density.