Comparison of the stellar structure of the giant stars in MESA and the relaxed star in PHANTOM. The upper, middle, and lower panels represent the enclosed mass, density, and pressure at different radii, respectively. Blue, red, and green lines represent RG1, RG2, and RG3, respectively. Dashed and solid lines indicate stars in MESA and PHANTOM, respectively. Since the core is replaced by a sink particle, there is a difference at low radius.