(a) Radial profiles of the superadiabaticity δ(r) defined by Eq. (2) for different values of the bulk superadiabaticity δ_cz. The superadiabaticity in the near-surface layer is fixed to δ_sf = 10⁻³. (b) Dispersion relations of the HHS22 modes computed for different superadiabaticity profiles. The observed frequencies reported by hanson2022 are denoted by gray diamonds. (c) Meridional eigenfunctions from the case with weakly subadiabatic bulk convection zone (δ_cz = −5 × 10⁻⁷). Black solid and gray dashed curves show the locations of the critical latitudes (by differential rotation) and the turning surfaces (by subadiabatic stratification), respectively.