Panel (a): relationship between ℳ_★, T and ⟨t_★, B⟩_ℳ (large markers) and the parent disk (⟨t_★, D⟩_ℳ, small markers). Panel (b): comparison of ℳ_★, T and the mean age difference between bulge and disk components. In panel (b), the regions shaded blue and red depict the age difference between the hot and cold orbit components within the effective radius as a function of stellar mass for two different models, as derived by Jin et al. (2024). Markers follow the same coding as in Fig. 2.