TY - JOUR

T1 - Long Baseline Observations of the HD 100546 Protoplanetary Disk with ALMA

AU - Perez, Sebastian

AU - Casassus, Simon

AU - Hales, Antonio

AU - Marino, Sebastian

AU - Cheetham, Anthony

AU - Zurlo, Alice

AU - Cieza, Lucas

AU - Dong, Ruobing

AU - Alarcon, Felipe

AU - Benitez-Llambay, Pablo

AU - Fomalont, Ed

AU - Avenhaus, Henning

PY - 2020/1/20

Y1 - 2020/1/20

N2 - Using the Atacama Large Millimeter/submillimeter Array, we observed the young Herbig star HD 100546, host to a prominent disk with a deep, wide gap in the dust. The high-resolution 1.3 mm continuum observation reveals fine radial and azimuthal substructures in the form of a complex maze of ridges and trenches sculpting a dust ring. The (CO)-C-12(2-1) channel maps are modulated by wiggles or kinks that deviate from Keplerian kinematics particularly over the continuum ring, where deviations span 90 degrees in azimuth, covering similar to 5 km s(-1). The most pronounced wiggle resembles the imprint of an embedded massive planet of at least 5 M-Jup predicted from previous hydrodynamical simulations. Such a planet is expected to open a deep gap in both gas and dust density fields within a few orbital timescales, yet the kinematic wiggles lie near ridges in the continuum. The lesser strength of the wiggles in the (CO)-C-13 and (CO)-O-18 isotopologues show that the kinematic signature weakens at lower disk heights, and suggests qualitatively that it is due to vertical flows in the disk surface. Within the gap, the velocity field transitions from Keplerian to strongly non-Keplerian via a twist in position angle, suggesting the presence of another perturber and/or an inner warp. We also present Very Large Telescope/SPHERE sparse aperture masking data that recover scattered light emission from the gap's edges but show no evidence for signal within the gap, discarding a stellar binary origin for its opening.

AB - Using the Atacama Large Millimeter/submillimeter Array, we observed the young Herbig star HD 100546, host to a prominent disk with a deep, wide gap in the dust. The high-resolution 1.3 mm continuum observation reveals fine radial and azimuthal substructures in the form of a complex maze of ridges and trenches sculpting a dust ring. The (CO)-C-12(2-1) channel maps are modulated by wiggles or kinks that deviate from Keplerian kinematics particularly over the continuum ring, where deviations span 90 degrees in azimuth, covering similar to 5 km s(-1). The most pronounced wiggle resembles the imprint of an embedded massive planet of at least 5 M-Jup predicted from previous hydrodynamical simulations. Such a planet is expected to open a deep gap in both gas and dust density fields within a few orbital timescales, yet the kinematic wiggles lie near ridges in the continuum. The lesser strength of the wiggles in the (CO)-C-13 and (CO)-O-18 isotopologues show that the kinematic signature weakens at lower disk heights, and suggests qualitatively that it is due to vertical flows in the disk surface. Within the gap, the velocity field transitions from Keplerian to strongly non-Keplerian via a twist in position angle, suggesting the presence of another perturber and/or an inner warp. We also present Very Large Telescope/SPHERE sparse aperture masking data that recover scattered light emission from the gap's edges but show no evidence for signal within the gap, discarding a stellar binary origin for its opening.

KW - CO line emission

KW - Dust continuum emission

KW - Circumstellar dust

KW - Exoplanet detection methods

KW - Protoplanetary disks

KW - Planet formation

KW - PLANET

U2 - 10.3847/2041-8213/ab6b2b

DO - 10.3847/2041-8213/ab6b2b

M3 - Letter

VL - 889

JO - The Astrophysical Journal Letters

JF - The Astrophysical Journal Letters

SN - 2041-8205

IS - 1

M1 - L24

ER -