¹²CO individual channel maps at different line-of-sight velocities. The gray filled white contours trace the model of an infalling shell with r_d = 700 au and θ₀ = 70°. The contours are not filled when the emission is arising from the back side of the infalling shell. The contour of the slow wide-angle component is indicated by the white dashed line. The color scale is the same for all the channel maps.