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Title: A Potential Site for Wide-orbit Giant Planet Formation in the IM Lup Disk
Abstract

The radial transport, or drift, of dust has taken a critical role in giant planet formation theory. However, it has been challenging to identify dust drift pileups in the hard-to-observe inner disk. We find that the IM Lup disk shows evidence that it has been shaped by an episode of dust drift. Using radiative transfer and dust dynamical modeling we study the radial and vertical dust distribution. We find that high dust drift rates exceeding 110MMyr−1are necessary to explain both the dust and CO observations. Furthermore, the bulk of the large dust present in the inner 20 au needs to be vertically extended, implying high turbulence (αz≳ 10−3) and small grains (0.2–1 mm). We suggest that this increased level of particle stirring is consistent with the inner dust-rich disk undergoing turbulence triggered by the vertical shear instability. The conditions in the IM Lup disk imply that giant planet formation through pebble accretion is only effective outside of 20 au. If such an early, high-turbulence inner region is a natural consequence of high dust drift rates, then this has major implications for understanding the formation regions of giant planets including Jupiter and Saturn.

 
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Award ID(s):
1907653
NSF-PAR ID:
10398574
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
944
Issue:
2
ISSN:
2041-8205
Format(s):
Medium: X Size: Article No. L53
Size(s):
["Article No. L53"]
Sponsoring Org:
National Science Foundation
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