Vertical cut along the dotted line plotted in Fig. 4. From top to bottom, left to right: temperature, density, vertical components of magnetic field and velocity, sum of resistive and viscous heating terms and total line emissivity for 1394 Å. The red line marks the formation height of Hα line core. The green line marks the formation height of the Hα blue wing at v_D = −53 km s⁻¹. Black vertical lines, from left to right, mark the positions of the red, green, and white pixels in Fig. 4, respectively.