Structural comparison between the optimal seismic model of KIC 08626021 derived by Giammichele et al. (2018; in black) and the new optimal seismic solution obtained with improved models that include neutrino cooling (up to second-order approximation; in red). Top panel: composition stratification for helium, carbon, and oxygen. Lower panel: logarithm of the squared Brunt-Väisälä and ℓ = 1, 2 Lamb frequencies (logN² and ).