A new planet candidate detected in a dust gap of the disc around HD 163296 through localised kinematic signatures. An observational validation of the Discminer

Abstract

We report the robust detection of coherent, localised deviations from Keplerian rotation possibly associated with the presence of two giant planets embedded in the disc around HD 163296. The analysis is performed using the DISCMINER channel-map modelling framework on ${}^{12}$CO $J=2-1$ DSHARP data. Not only orbital radius, but also azimuth of the planets are retrieved by our technique. One of the candidate planets, detected at $R=94\pm 6$ au, $\varphi =50\pm 3^{\circ }$ (P94), is near the centre of one of the gaps in dust continuum emission, and is consistent with a planet mass of 1 ${\mathrm{M}}_{\mathrm{Jup}}$. The other planet, located at $R=261\pm 4$ au, $\varphi =57\pm 1^{\circ }$ (P261), is in the region where a velocity kink was previously observed in ${}^{12}$CO channel maps. Also, we provide a simultaneous description of the height and temperature of the upper and lower emitting surfaces of the disc, and propose the line width as a solid observable to track gas substructure. Using azimuthally averaged line width profiles we detect gas gaps at $R=38$ au, $R=88$ au, and $R=136$ au, closely matching the location of their dust and kinematical counterparts. Furthermore, we observe strong azimuthal asymmetries in line widths around the gas gap at $R=88$ au, possibly linked to turbulent motions driven by the P94 planet. Our results confirm that the DISCMINER is capable of finding localised, otherwise unseen velocity perturbations thanks to its robust statistical framework, but also that it is well suited for studies of the gas properties and vertical structure of protoplanetary discs.

22 pages, 14 figures, 1 table. Accepted for publication in ApJ

References in corpus (17)

• Two accreting protoplanets around the young star PDS 70
• Observations of Protoplanetary Disk Structures
• Molecules with ALMA at Planet-forming Scales (MAPS) I: Program Overview and Highlights
• A Three-Dimensional View of Turbulence: Constraints on Turbulent Motions in the HD 163296 Protoplanetary Disk using DCO${}^{+}$
• Meridional flows in the disk around a young star
• Direct mapping of the temperature and velocity gradients in discs. Imaging the vertical CO snow line around IM Lupi
• Protoplanetary disk masses from CO isotopologues line emission
• Nine localised deviations from Keplerian rotation in the DSHARP circumstellar disks: Kinematic evidence for protoplanets carving the gaps
• Formation of a disc gap induced by a planet: Effect of the deviation from Keplerian disc rotation
• On the formation of multiple concentric rings and gaps in protoplanetary disks
• The efficiency of dust trapping in ringed proto-planetary discs
• The Disc Miner I: A statistical framework to detect and quantify kinematical perturbations driven by young planets in discs
• Midplane temperature and outer edge of the protoplanetary disk around HD 163296
• Observational Signatures of Tightly Wound Spirals Driven by Buoyancy Resonances in Protoplanetary Disks
• The theory of kinks -- I. A semi-analytic model of velocity perturbations due to planet-disc interaction
• Constraining Protoplanetary Disk Accretion and Young Planets Using ALMA Kinematic Observations
• Visualizing the Kinematics of Planet Formation

Cited by in corpus (42)

• Dust growth and evolution in protoplanetary disks
• Distribution of solids in the rings of the HD 163296 disk: a multiwavelength study
• Directly tracing the vertical stratification of molecules in protoplanetary disks
• Dynamical mass measurements of two protoplanetary discs
• The Disc Miner II: Revealing Gas substructures and Kinematic signatures from Planet-disc interaction through line profile analysis
• Gas temperature structure across transition disk cavities
• Mapping the Complex Kinematic Substructure in the TW Hya Disk
• Kinematics and brightness temperatures of transition discs -- A survey of gas substructures as seen with ALMA
• exoALMA III: Line-intensity Modeling and System Property Extraction from Protoplanetary Disks
• Mapping Protoplanetary Disk Vertical Structure with CO Isotopologue Line Emission
• Rotation curves in protoplanetary disks with thermal stratification
• A kinematically detected planet candidate in a transition disk
• Population Synthesis Models Indicate a Need for Early and Ubiquitous Disk Substructures
• Mapping the Planetary Wake in HD 163296 with Kinematics
• Searching for H${}_{\alpha }$-emitting sources in the gaps of five transitional disks. SPHERE/ZIMPOL high-contrast imaging
• ISPY-NACO Imaging Survey for Planets around Young stars. The demographics of forming planets embedded in protoplanetary disks
• exoALMA. VI. Rotating under Pressure: Rotation curves, azimuthal velocity substructures, and pressure variations
• Chemical footprints of giant planet formation. Role of planet accretion in shaping the C/O ratio of protoplanetary disks
• Vertically extended and asymmetric CN emission in the Elias 2-27 protoplanetary disk
• A localized kinematic structure detected in atomic carbon emission spatially coincident with a proposed protoplanet in the HD 163296 disk
• ALMA high-resolution observations unveil planet formation shaping molecular emission in the PDS 70 disk
• exoALMA. XVII. Characterizing the Gas Dynamics around Dust Asymmetries
• Kinematic and thermal signatures of the directly imaged protoplanet candidate around Elias 2-24
• DBNets: A publicly available deep learning tool to measure the masses of young planets in dusty protoplanetary discs
• Three-dimensional transport of solids in a protoplanetary disk containing a growing giant planet
• FAUST. XVIII. Evidence for annular substructure in a very young Class 0 disk
• A dichotomy in group II Herbig disks: ALMA gas disk height measurements show both shadowed large vertically extended disks and compact flat disks
• exoALMA. VIII. Probabilistic Moment Maps and Data Products using Non-parametric Linear Models
• Testing velocity kinks as a planet-detection method: Do velocity kinks in surface gas emission trace planetary spiral wakes in the midplane continuum?
• Millimeter emission in photoevaporating disks is determined by early substructures
• Combining reference-star and angular differential imaging for high-contrast imaging of extended sources
• HD 163296 and its Giant Planets: Creation of Exo-comets, Interstellar Objects and Transport of Volatile Material
• Dust Rings and Cavities in the Protoplanetary Disks around HD 163296 and DoAr 44
• A complete Herbig disk mass survey in Orion
• Circumplanetary Disk Candidate in the Disk of HD 163296 Traced by Localized Emission from Simple Organics
• FAUST. XXVIII. High-Resolution ALMA Observations of Class 0/I Disks: Structure, Optical Depths, and Temperatures
• The Dynamic Inner Disk of a Planet Forming Star
• exoALMA XXI: The Morphology and Dynamics of Vertical Flows
• exoALMA XX: Tomographic Detection of Embedded Planets in Protoplanetary Disks
• A tension between dust and gas radii: the role of substructures and external photoevaporation in protoplanetary disks
• Protoplanetary Disk Chemistry
• CO Line Emission Surfaces and Vertical Structure in Mid-Inclination Protoplanetary Disks