Magnetic field strength and inclination at the apex of the loop at x = 75 Mm of Chen et al. (2014, 2015). Panel a: induced magnetic field: color-coded together with magnetic field vectors B^ind in y-z plane. We note that the positive x direction is pointing out of the plane of view. Panel b: angle γ between current density J and the magnetic field B, see Eq. (2). The locations, where the magnetic field lines Fig. 3 breach through the plane are marked with yellow crosses. We refer to Sect. 3.3.