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Title: SO and SiS Emission Tracing an Embedded Planet and Compact 12 CO and 13 CO Counterparts in the HD 169142 Disk
Abstract Planets form in dusty, gas-rich disks around young stars, while at the same time, the planet formation process alters the physical and chemical structure of the disk itself. Embedded planets will locally heat the disk and sublimate volatile-rich ices, or in extreme cases, result in shocks that sputter heavy atoms such as Si from dust grains. This should cause chemical asymmetries detectable in molecular gas observations. Using high-angular-resolution ALMA archival data of the HD 169142 disk, we identify compact SOJ= 88− 77and SiSJ= 19 − 18 emission coincident with the position of a ∼ 2MJupplanet seen as a localized, Keplerian NIR feature within a gas-depleted, annular dust gap at ≈38 au. The SiS emission is located along an azimuthal arc and has a morphology similar to that of a known12CO kinematic excess. This is the first tentative detection of SiS emission in a protoplanetary disk and suggests that the planet is driving sufficiently strong shocks to produce gas-phase SiS. We also report the discovery of compact12CO and13COJ= 3 − 2 emission coincident with the planet location. Taken together, a planet-driven outflow provides the best explanation for the properties of the observed chemical asymmetries. We also resolve a bright, azimuthally asymmetric SO ring at ≈24 au. While most of this SO emission originates from ice sublimation, its asymmetric distribution implies azimuthal temperature variations driven by a misaligned inner disk or planet–disk interactions. Overall, the HD 169142 disk shows several distinct chemical signatures related to giant planet formation and presents a powerful template for future searches of planet-related chemical asymmetries in protoplanetary disks.  more » « less
Award ID(s):
1907832
PAR ID:
10474384
Author(s) / Creator(s):
; ;
Publisher / Repository:
arXiv
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
952
Issue:
1
ISSN:
2041-8205
Page Range / eLocation ID:
L19
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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