Mapsof GFPI averaged LOS velocity (left) and horizontal proper motions (right) around the leading spot P₁, where color-coded vectors indicate magnitude and direction of the horizontal flows. The black contours mark the umbra-penumbra boundary, whereas the white contours denote the penumbra-granulation boundary. The contours shown here and in all subsequent figures are extracted from the GFPI broad-band image. The two black arcs mark the penumbral sector PS.