Dependence of the resultant planetesimal belt on k_SI. Left and right panels: cases of different given disk structures (Disk 2 and Disk 3, respectively; Table 1). Top panels: given disk structures. Bottom three panels: the same combination of F_p/g and the disk structure but different k_SI. The dashed gray lines in the top panels show the analytically derived critical α_mid/α_acc for a given F_p/g, indicating that disks having smaller α_mid/α_acc than the critical one are expected to develop the ND mode (no dependence on k_SI; Eq. (11)). The blue, green, red, and black lines represent time evolution. By t ≃ 3 x 10⁵ years, all cases reach a steady-state in ρ_p/ρ_g and the planetesimals keep forming in a ring with a constant width. The gray lines represent the midplane pebble-togas ratio, ρ_p/ρ_g, at the steady-state shown in the right axis. Here, τ_s = 0.1 and M_g = 10⁻⁸ M_⊙ yr⁻¹ are used.