Diagnostics of the spherically averaged radial velocity for the standard model st26gm07n001. Top left: radial velocity as a function of time and radial coordinates, where the solid and dashed lines mark the radius and 80% of the radius, respectively. Bottom left: average and standard deviation of the radial velocity (in blue and shaded in grey, respectively) within the layer of 80–100% of the radius. Top right: FFT power spectrum (values are clipped to the maximum power calculated in between the 80–100% of the radius) as a function of the frequency and radial coordinates. Bottom right: averaged and normalised FFT power spectrum across the aforementioned layer. Here the shaded region is the extent over which the weighted averaging (see text) to get a characteristic pulsation frequency was done, while the solid and dashed black vertical lines indicate the computed characteristic frequency and its spread, respectively.