(a) Time evolution of the kinetic and magnetic energies for run d1. Three phases, (I) kinematic, (II) weak nonlinear, and (III) saturated, of the α² dynamo are highlighted. (b) Kinetic and magnetic energy spectra are shown from the plane at z = −0.1L₀, during the kinematic and saturated phases. The black dashed line shows the forcing wavenumber k_f. (c) Spacetime diagram of the mean magnetic field components. Magnetic fields are first averaged over the x–z plane to define ﹩{\langle {B}_{x}\rangle }_{xz}﹩ and ﹩{\langle {B}_{z}\rangle }_{xz}﹩. These quantities are then normalized by their corresponding rms values ﹩\sqrt{{\langle {\langle {B}_{x}\rangle }_{xz}^{2}\rangle }_{y}}﹩ and ﹩\sqrt{{\langle {\langle {B}_{z}\rangle }_{xz}^{2}\rangle }_{y}}﹩, respectively. (d) Vertical profile of horizontally averaged plasma beta β(z), in the saturated phase. The red dashed line marks z = −0.1L₀.