Profiles of the superadiabaticity, δ. (a–d) Vertical profiles of δ for different Co_*. Blue and red curves represent the results from HD and MHD simulations. (e) Volume-averaged values of superadiabaticity, $\overline{\delta }$, as a function of Co_*. The inset shows the magnitudes of the subadiabatic layers near the bottom of the convection zone, D_sub = ∫₀^d_sub|δ|dz (with d_sub being the height below which the mean stratification is subadiabatic), denoted by the shaded areas in panels a–d.