Panel a: jet base appearing as brightening with an arch-shape in between the positive (green contours) and negative (blue contours) in AIA 94 Å. Panel b: HMI Vector magnetic field map with the same FOV as of the (a). The white square is the FOV for the Figs. 11a and b. The colour bar indicates the vertical magnetic field strength and the arrow on the right the strength of the horizontal magnetic field in the map in (b).