Density structure of the MESA models (blue) compared to a polytropic structure (red dash). The MESA models are: Standard model at 0.13 Gyr (h0-3, top left) and at 8.1 Gyr (h0-11, top right) as well as the set 2 10x heated model at 10.5 Gyr (h10-22, bottom). The polytropes are labeled with their corresponding index, and their central density was chosen to coincide with that of the MESA models for illustration purposes. The density is given in units of g cm⁻³.