Top panel: period spectrum corresponding to the optimal seismic model obtained for TIC 278659026 and represented in terms of the reduced period spacing, (in s) as a function of reduced period, (in s). Open squares connected by plain segments show the ℓ = 1 series of modes and open triangles connected by dotted segments are ℓ = 2 modes. The range of radial orders covered spans k = 5 to k = 60, as in Table B.1. Plain and dotted vertical lines indicate the reduced periods of the observed modes matched to ℓ = 1 and ℓ = 2 modes, respectively. When two observed modes of same degree have consecutive radial orders, an observed reduced period spacing is also indicated (filled squares and filled triangles for ℓ = 1 and ℓ = 2 modes, respectively). Bottom panel: same as above, but for the logarithm of the kinetic energy (or inertia), log E_kin, of the modes as a function of reduced period.