Possible evidence of ongoing planet formation in AB Aurigae. A showcase of the SPHERE/ALMA synergy

Abstract

Context. Planet formation is expected to take place in the first million years of a planetary system through various processes, which remain to be tested through observations. Aims. With the recent discovery, using ALMA, of two gaseous spiral arms inside the 120 au cavity and connected to dusty spirals, the famous protoplanetary disk around AB Aurigae presents a strong incentive for investigating the mechanisms that lead to giant planet formation. A candidate protoplanet located inside a spiral arm has already been claimed in an earlier study based on the same ALMA data. Methods. We used SPHERE at the Very Large Telescope (VLT) to perform near-infrared (IR) high-contrast imaging of AB Aur in polarized and unpolarized light in order to study the morphology of the disk and search for signs of planet formation. Results. SPHERE has delivered the deepest images ever obtained for AB Aur in scattered light. Among the many structures that are yet to be understood, we identified not only the inner spiral arms, but we also resolved a feature in the form of a twist in the eastern spiral at a separation of about 30 au. The twist of the spiral is perfectly reproduced with a planet-driven density wave model when projection effects are accounted for. We measured an azimuthal displacement with respect to the counterpart of this feature in the ALMA data, which is consistent with Keplerian motion on a 4-yr baseline. Another point sxce is detected near the edge of the inner ring, which is likely the result of scattering as opposed to the direct emission from a planet photosphere. We tentatively derived mass constraints for these two features. Conclusions. The twist and its apparent orbital motion could well be the first direct evidence of a connection between a protoplanet candidate and its manifestation as a spiral imprinted in the gas and dust distributions.

arXiv commentaccepted in Astronomy and Astrophysics, 8 pages, 5 figures

References in corpus (37)

• Gaia Data Release 2. Summary of the contents and survey properties
• Detection and Characterization of Exoplanets and Disks using Projections on Karhunen-Loeve Eigenimages
• Planet-disk interaction and orbital evolution
• SPHERE: the exoplanet imager for the Very Large Telescope
• Two accreting protoplanets around the young star PDS 70
• Discovery of Small-Scale Spiral Structures in the Disk of SAO 206462 (HD 135344B): Implications for the Physical State of the Disk from Spiral Density Wave Theory
• Investigating fragmentation conditions in self-gravitating accretion discs
• Asymmetric features in the protoplanetary disk MWC758
• Direct Imaging of Fine Structures in Giant Planet Forming Regions of the Protoplanetary Disk around AB Aurigae
• Observational Signatures of Planets in Protoplanetary Disks II: Spiral Arms Observed in Scattered Light Imaging Can be Induced by Planets
• Impact of angular differential imaging on circumstellar disk images
• Nonlinear propagation of planet-generated tidal waves
• HST/ACS Coronagraphic Imaging of the Circumstellar Disk around HD1415659A
• Accreting Circumplanetary Disks: Observational Signatures
• Sub-arcsec imaging of the AB Aur molecular disk and envelope at millimeter wavelengths: a non Keplerian disk
• The polarimetric imaging mode of VLT/SPHERE/IRDIS II: Characterization and correction of instrumental polarization effects
• Global hydromagnetic simulations of a planet embedded in a dead zone: gap opening, gas accretion and formation of a protoplanetary jet
• Measuring Protoplanetary Disk Accretion with H I Pf-beta
• Astrometric and photometric accuracies in high contrast imaging: The SPHERE speckle calibration tool (SpeCal)
• The circumstellar disk of AB Aurigae: evidence for envelope accretion at late stages of star formation?
• Planet Formation in AB Aurigae: Imaging of the inner gaseous Spirals observed inside the Dust Cavity
• The polarimetric imaging mode of VLT/SPHERE/IRDIS I: Description, data reduction and observing strategy
• Spiral arms in the disk of HD 142527 from CO emission lines with ALMA
• Millimeter imaging of MWC 758: probing the disk structure and kinematics
• Planet-driven spiral arms in protoplanetary disks: I. Formation mechanism
• An M Dwarf Companion and Its Induced Spiral Arms in the HD 100453 Protoplanetary Disk
• The Solar-System-Scale Disk Around AB Aurigae
• The Case of AB Aurigae's Disk in Polarized Light: Is There Truly a Gap?
• SPHERE IRDIS and IFS astrometric strategy and calibration
• Accretion Properties of PDS 70b with MUSE
• Multiple spiral patterns in the transitional disk of HD 100546
• An Ordered Magnetic Field in the Protoplanetary Disk of AB Aur Revealed by Mid-Infrared Polarimetry
• Spirals inside the millimeter cavity of transition disk SR 21
• Dynamical Gaseous Rings in Global Simulations of Protoplanetary Disk Formation
• Spatially resolved spectroscopy of the debris disk HD 32297: Further evidence of small dust grains
• Gas accretion within the dust cavity in AB Aur
• Constraining the Movement of the Spiral Features and the Locations of Planetary Bodies within the AB Aur System

Cited by in corpus (48)

• Images of Embedded Jovian Planet Formation At A Wide Separation Around AB Aurigae
• Constraining the Nature of the PDS 70 Protoplanets with VLTI/GRAVITY
• On the diversity of asymmetries in gapped protoplanetary disks
• Disk Evolution Study Through Imaging of Nearby Young Stars (DESTINYS): Late infall causing disk misalignment and dynamic structures in SU Aur
• Misaligned disks induced by infall
• A search for a 5th planet around HR 8799 using the star-hopping RDI technique at VLT/SPHERE
• Gravitational instability in a planet-forming disk
• Kinematics and brightness temperatures of transition discs -- A survey of gas substructures as seen with ALMA
• HST/WFC3 H$\alpha$ Direct-Imaging Detection of a Point-like Source in the Disk Cavity of AB Aur
• Protoplanetary disks in $K_s$-band total intensity and polarized light
• The IGRINS YSO Survey I. Stellar parameters of pre-main sequence stars in Taurus-Auriga
• AB Aur, a Rosetta stone for studies of planet formation (I): chemical study of a planet-forming disk
• Herbig Stars: A Quarter Century of Progress
• Binary-induced spiral arms inside the disc cavity of AB Aurigae
• Searching for H${}_{\alpha }$-emitting sources in the gaps of five transitional disks. SPHERE/ZIMPOL high-contrast imaging
• Mapping the merging zone of late infall in the AB Aur planet-forming system
• Spiral Arm Pattern Motion in the SAO 206462 Protoplanetary Disk
• Spirals, shadows & precession in HD 100453 -- II. The hidden companion
• Signs of late infall and possible planet formation around DR Tau using VLT/SPHERE and LBTI/LMIRCam
• The water-ice feature in near-infrared disk-scattered light around HD 142527: Micron-sized icy grains lifted up to the disk surface?
• Constrained Reference Star Differential Imaging: Enabling High-Fidelity Imagery of Highly Structured Circumstellar Disks
• Large amplitude periodic outbursts and long period variables in the VVV VIRAC2-$\beta$ database
• Observational signatures of eccentric Jupiters inside gas cavities in protoplanetary discs
• A Simple Time-Dependent Method for Calculating Spirals: Applications to Eccentric Planets in Protoplanetary discs
• Spatially correlated stellar accretion in the Lupus star forming region: Evidence for ongoing infall from the interstellar medium
• The centimeter emission from planet-forming disks in Taurus
• Detection of Near-Infrared Water Ice at the Surface of the (pre)Transitional Disk of AB Aur: Informing Icy Grain Abundance, Composition, and Size
• AB Aurigae: Possible evidence of planet formation through the gravitational instability
• Apparent motion of the circumstellar envelope of CQ Tau in scattered light
• Disk Evolution Study Through Imaging of Nearby Young Stars (DESTINYS): HD 34700 A unveils an inner ring
• SO as shock tracer in protoplanetary disks: the AB Aurigae case
• Mid-infrared evidence for iron-rich dust in the multi-ringed inner disk of HD 144432
• Quantitative polarimetry for the transition disk in RX J1604.3-213010
• Characterization of debris disks observed with SPHERE
• The likelihood of not detecting cavity-carving companions in transition discs -- A statistical approach
• Multiband polarimetric imaging of HD 34700 with SCExAO/CHARIS
• Probing Photon Statistics in Adaptive Optics Images with SCExAO/MEC
• Spatially resolving polycyclic aromatic hydrocarbons in Herbig Ae disks with VISIR-NEAR at the VLT
• LBT search for companions and sub-structures in the (pre)transitional disk of AB Aurigae
• UV-processing of icy pebbles in the outer parts of VSI-turbulent disks
• Dynamics of magnetized accretion disks of young stars
• High-contrast integral field spectropolarimetry of planet-forming disks with SCExAO/CHARIS
• An HST/STIS View of Protoplanetary Disks in Upper Scorpius: Observations of Three Young M-Stars
• Molecules with ALMA at Planet-forming Scales (MAPS) XIX. Spiral Arms, a Tail, and Diffuse Structures Traced by CO around the GM Aur Disk
• A multiwavelength analysis of the spiral arms in the protoplanetary disk around WaOph 6
• The asymmetric structure of the inner disc around HD 142527 A with VLTI/MATISSE
• Observation of an Accreting Planetary-Mass Companion with Signs of Disk-Disk Interaction in Orion
• Gravitational instability in planet-forming discs