Аннотация
Protoplanetary disks are dynamic objects, within which dust grains and gas
are expected to be redistributed over large distances. Evidence for this
redistribution is seen both in other protoplanetary disks and in our own Solar
System, with high-temperature materials thought to originate close to the
central star found in the cold, outer regions of the disks. While models have
shown this redistribution is possible through a variety of mechanisms, these
models have generally ignored the possible growth of solids via grain-grain
collisions that would occur during transit. Here we investigate the interplay
of coagulation and radial and vertical transport of solids in protoplanetary
disks, considering cases where growth is limited by bouncing or by
fragmentation. We find that in all cases, growth effectively limits the ability
for materials to be carried outward or preserved at large distances from the
star. This is due to solids being incorporated into large aggregates which
drift inwards rapidly under the effects of gas drag. We discuss the
implications for mixing in protoplanetary disks, and how the preservation of
high temperature materials in outer disks may require structures or outward
flow patterns to avoid them being lost via radial drift.
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