Stellar core radius versus stellar mass as predicted by the simple model presented in Sect. 3. Each line shows the variation in r_★c with M_★ when the DM halo mass goes from 10⁷ to 10¹⁴ M_⊙. The type of line depends on whether the corresponding profile is in the core-formation phase (t_age < t_c; dashed line) or the core-collapse phase (t_age > t_c; solid line). The parameters that define the cross sections are given in the inset, with the actual velocity dependence represented in Fig. 5 with the same color code employed here. Observations of r_★c versus M_★ are represented as symbols, each one corresponding to an individual object. The measurements are labeled in the inset, with the UFDs analyzed in this work appearing under the label SA+24. The link between labels and references is specified in Appendix C. The figure also includes the theoretical expectations from stellar feedback on CDM halos from Lazar et al. (2020, the gray band and solid line).