Left panel: wave spectrum overlaid with the function used to filter waves corresponding to the radial order p₂. Middle and right panels: travel-time shifts between waves in the starting and true flow models for supergranule SG2, computed at all receivers for different radial orders. The horizontal location of the source is indicated by the dashed vertical line. The horizontal flow field of the supergranule is indicated by the colored patch in the background, where red indicates outflows away from the cell center and blue indicates inflows toward the cell center.