Initial profiles for the narrow composition gradient, showing specific entropy, temperature, and composition as functions of normalized mass. The colors blue, orange, and yellow correspond to different primordial entropies. The dotted, solid, and dashed lines correspond to planets with a mass of 5 Μ_⊕, 10 Μ_⊕, and 15 Μ_⊕, respectively. Top: Specific entropy vs. normalized mass of the initial model for the narrow composition profile. The blue (cold), orange (warm), and yellow (hot) colors represent different initial entropies. The dotted, solid, and dashed lines correspond to planets with a mass of 5 Μ_⊕, 10 Μ_⊕, and 15 M_⊕, respectively. The metallicity of the composition profile is represented by a black line, with its y-axis on the right-hand side. Bottom: Temperature vs. normalized mass of the initial model for the narrow composition profile. The black line shows the metallicity.