Integrated residence time for monomers of s_m = 5 × 10⁻⁸ m (blue), 3 × 10⁻⁴ m (orange), and 3 × 10⁻³ m (green) as a function of height z at r = 10 AU. The solid lines denote the histogram obtained from the trajectories of 10³ monomers combined, whereas the dashed lines are the theoretical vertical density profiles expected from Eq. (8). The vertical dashed lines depict the locations where z = H_d for each monomer size.