Same as Fig. 3 but with τ_SI = 10³T_K. The left and right panels represent the profiles with α = 10^−3.4 and 10⁻⁴, respectively. In the left panel, the profiles with τ_SI = 10 yr are also plotted as the dotted curves. All planetesimals form by streaming instability when α = 10 −3.4. In the right panel, we plot the mass of the planetesimals formed by streaming instability (red) and by mutual collision (green). The blue dashed line represents the slope of the dust mass assuming constant loss with . The green dashed line represents the slope of the cumulative mass of the dust drifting into the planetesimal formation place with the same mass flux.