Vertical profiles of the vertical velocity when the plasmoids form for z_rec = 2 Mm. Shown for five moments in time in the late stage of the simulations, for the three models: 2flα (left panel), 2fl (middle panel), and MHD (right panel). For the two-fluid models (left and middle panels), we show the velocity of charges. The linear fit of the velocity profile around the reconnection point (where the velocity changes sign) is shown by a black line and the value of the slope is indicated at the top of each panel.