Same as Fig. 5, but for different dynamical models. Top panel: model N2d-MRI without prescribed MF effects; the radial scale length of the magnetic field is ≃10  kpc. Middle panel: model N2d-noD without α effect, but including turbulent diffusion (which suppresses the MRI for ). Bottom panel: model N3d with combined α effect and MRI, at t = 3.9 Gyr, i.e., when the S0 mode dominates (cf. Fig. 9b).