Location of the furthest cores formed by reaching M_iso, marked by the height of the colored bar, for different scenarios (specified in Table 2) and for protoplanets initialized at different formation times, t_0,p, in each panel. Horizontal green lines in the background illustrate the location of the observed gaps in protoplanetary disks that could be caused by planetary cores placed in the same location (Data from http://ppvii.org/chapter/12/figure7.txt/). Whent_0,p = 0.2 Myr (top-left panel), favorable disk parameters for forming distant cores up to ~ R₁/2 are high St, high Z₀ and low α_t. “hst” runs with St = 0.06 also show that when initial protoplanets are injected late (t_0,p > 0.5 Myr, bottom panels) in disks with R₁ = 100 AU, the pebble flux by that point is too weak to grow wide-orbit cores. We note that for R₁ = 300 AU, the t_0,p = 0.7 Myr case is more consistent with the pebble growth timescale in outer disk (see Fig. 2). Overall, many observed gaps in protoplanetary disks could be caused by planetary cores, but the most distant gaps could only form in disks with high initial metallicity and a large disk size (see Sect. 5.2 for discussion).