Half-mass radius, R_*, 1/2 plotted against M_⋆. The rows show variations in the two SN-related parameters A_SN1 and A_SN2 and the two AGN parameters BH_RE and Q_T. The green lines represent the reference CAMELS simulation. Simulation snapshots at z = 0, z = 0.5, z = 1, z = 1.5, and z = 2 are displayed from left to right. The medians in stellar mass bins are shown. The dark and light grey regions indicate radii smaller than the softening length ϵ_min and 2 × ϵ_min, respectively.