Gas temperature structure across transition disk cavities

Abstract

[Abridged] Most disks observed at high angular resolution show substructures. Knowledge about the gas surface density and temperature is essential to understand these. The aim of this work is to constrain the gas temperature and surface density in two transition disks: LkCa15 and HD 169142. We use new ALMA observations of the ${}^{13}$CO $J=6-5$ transition together with archival $J=2-1$ data of ${}^{12}$CO, ${}^{13}$CO and C${}^{18}$O to observationally constrain the gas temperature and surface density. Furthermore, we use the thermochemical code DALI to model the temperature and density structure of a typical transition disk. The $6-5/2-1$ line ratio in LkCa15 constrains the gas temperature in the emitting layers inside the dust cavity to be up to 65 K, warmer than in the outer disk at 20-30 K. For the HD 169142, the peak brightness temperature constrains the gas in the dust cavity of HD 169142 to be 170 K, whereas that in the outer disk is only 100 K. Models also show that a more luminous central star, a lower abundance of PAHs and the absence of a dusty inner disk increase the temperature of the emitting layers and hence the line ratio in the gas cavity. The gas column density in the LkCa15 dust cavity drops by a factor >2 compared to the outer disk, with an additional drop of an order of magnitude inside the gas cavity at 10 AU. In the case of HD 169142, the gas column density drops by a factor of 200$-$500 inside the gas cavity, which could be due to a massive companion of several M${}_{\mathrm{J}}$. The broad dust-depleted gas region from 10-68 AU for LkCa15 may imply several lower mass planets. This work demonstrates that knowledge of the gas temperature is important to determine the gas surface density and thus whether planets, and if so what kind of planets, are the most likely carving the dust cavities.

arXiv commentAccepted for publication in Astronomy and astrophysics

References in corpus (113)

• Gaia Data Release 2. Summary of the contents and survey properties
• An atomic and molecular database for analysis of submillimetre line observations
• The Disk Substructures at High Angular Resolution Project (DSHARP): I. Motivation, Sample, Calibration, and Overview
• Passive irradiated circumstellar disks with an inner hole
• Discovery of a planetary-mass companion within the gap of the transition disk around PDS 70
• Resolved Images of Large Cavities in Protoplanetary Transition Disks
• Gaps and Rings in an ALMA Survey of Disks in the Taurus Star-forming Region
• Photoelectric Emission from Interstellar Dust: Grain Charging and Gas Heating
• Multi-Scale CLEAN deconvolution of radio synthesis images
• The Disk Substructures at High Angular Resolution Project (DSHARP): II. Characteristics of Annular Substructures
• Two accreting protoplanets around the young star PDS 70
• Ring shaped dust accumulation in transition disks
• Protoplanetary Disk Structures in Ophiuchus II: Extension to Fainter Sources
• Observations of Protoplanetary Disk Structures
• Radiation thermo-chemical models of protoplanetary disks I. Hydrostatic disk structure and inner rim
• The Disk Substructures at High Angular Resolution Project (DSHARP): VII. The Planet-Disk Interactions Interpretation
• Gaps, Rings, and Non-Axisymmetric Structures in Protoplanetary Disks - From Simulations to ALMA Observations
• Evidence of fast pebble growth near condensation fronts in the HL Tau protoplanetary disk
• A Kinematical Detection of Two Embedded Jupiter Mass Planets in HD 163296
• Imaging of the CO Snow Line in a Solar Nebula Analog
• LkCa 15: A Young Exoplanet Caught at Formation?
• Accreting Protoplanets in the LkCa 15 Transition Disk
• Observational Signatures of Planets in Protoplanetary Disks I: Gaps Opened by Single and Multiple Young Planets in Disks
• Molecules with ALMA at Planet-forming Scales (MAPS) I: Program Overview and Highlights
• Protoplanetary disc evolution and dispersal: the implications of X-ray photoevaportion
• On planet formation in HL Tau
• The warm gas atmosphere of the HD 100546 disk seen by Herschel (Evidence of a gas-rich, carbon-poor atmosphere?)
• A Circumplanetary Disk Around PDS70c
• ALMA unveils rings and gaps in the protoplanetary system HD 169142: signatures of two giant protoplanets
• Resolved gas cavities in transitional disks inferred from CO isotopologues with ALMA
• Survival of molecular gas in cavities of transition disks (I. CO)
• The Radial Distribution of H2 and CO in TW Hya as Revealed by Resolved ALMA Observations of CO Isotopologues
• Transitional Disks as Signposts of Young, Multiplanet Systems
• A young protoplanet candidate embedded in the circumstellar disk of HD100546
• 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
• Volatile carbon locking and release in protoplanetary disks. A study of TW Hya and HD 100546
• The minimum mass of detectable planets in protoplanetary discs and the derivation of planetary masses from high resolution observations
• Submillimeter emission associated with candidate protoplanets
• Kinematic detection of a planet carving a gap in a protoplanetary disc
• Observations of edge-on protoplanetary disks with ALMA I. Results from continuum data
• Dust depleted inner disks in a large sample of transition disks through long-baseline ALMA observations
• Cold Disks: Spitzer Spectroscopy of Disks around Young Stars with Large Gaps
• Discovery of a Companion Candidate in the HD169142 Transition Disk and the Possibility of Multiple Planet Formation
• The Eccentric Cavity, Triple Rings, Two-Armed Spirals, and Double Clumps of the MWC 758 Disk
• Gas density drops inside dust cavities of transitional disks around young stars observed with ALMA
• Submillimeter lines from circumstellar disks around pre-main sequence stars
• Different dust and gas radial extents in protoplanetary disks: consistent models of grain growth and CO emission
• Particle Concentration At Planet Induced Gap Edges and Vortices: I. Inviscid 3-D Hydro Disks
• Gaps in the HD169142 protoplanetary disk revealed by polarimetric imaging: Signs of ongoing planet formation?
• The dispersal of protoplanetary discs I: A new generation of X-ray photoevaporation models
• A Spitzer c2d Legacy Survey to Identify and Characterize Disks with Inner Dust Holes
• Gas structure inside dust cavities of transition disks: Oph IRS 48 observed by ALMA
• Molecules with ALMA at Planet-forming Scales (MAPS) IV: Emission Surfaces and Vertical Distribution of Molecules
• Tracing Slow Winds from T Tauri Stars via Low Velocity Forbidden Line Emission
• Models of Chemistry, Thermal Balance and Infrared Spectra from Intermediate-Aged Disks around G and K stars
• ALMA hints at the presence of two companions in the disk around HD 100546
• GASPS - a Herschel survey of gas and dust in Protoplanetary Disks: Summary and Initial Statistics
• Embedded Protostars in the Dust, Ice, and Gas In Time (DIGIT) Key Program: Continuum SEDs, and an Inventory of Characteristic Far-Infrared Lines from PACS Spectroscopy
• New insights into the nature of transition disks from a complete disk survey of the Lupus star forming region
• ALMA imaging of the CO snowline of the HD 163296 disk with DCO+
• Imaging diagnostics for transitional discs
• Spatially extended PAHs in circumstellar disks around T Tauri and Herbig Ae stars
• PAH chemistry and IR emission from circumstellar disks
• Robustness of N2H+ as tracer of the CO snowline
• Dust unveils the formation of a mini-Neptune planet in a protoplanetary ring
• Complex Spiral Structure in the HD 100546 Transitional Disk as Revealed by GPI and MagAO
• No Clear, Direct Evidence for Multiple Protoplanets Orbiting LkCa 15: LkCa 15 bcd are Likely Inner Disk Signals
• The Distribution and Excitation of CH${}_3$CN in a Solar Nebula Analog
• Dust Evolution Can Produce Scattered Light Gaps in Protoplanetary Disks
• Imaging the Inner and Outer Gaps of the Pre-Transitional Disk of HD 169142 at 7 mm
• CO gas inside the protoplanetary disk cavity in HD 142527: disk structure from ALMA
• Methanol and its relation to the water snowline in the disk around the young outbursting star V883 Ori
• Homogeneous study of Herbig Ae/Be stars from spectral energy distributions and Gaia EDR3
• Kinematic detections of protoplanets: a Doppler-flip in the disk of HD100546
• An Optical/near-infrared investigation of HD 100546 b with the Gemini Planet Imager and MagAO
• On the gas temperature in circumstellar disks around A stars
• Spatial separation of small and large grains in the transitional disk around the young star IRS 48
• First results of the Herschel Key Program 'Dust, Ice and Gas in Time': Dust and Gas Spectroscopy of HD 100546
• Resolving the planet-hosting inner regions of the LkCa 15 disk
• Chemical Modelling of Young Stellar Objects, I. Method and Benchmarks
• Empirical Temperature Measurement in Protoplanetary Disks
• Inferring giant planets from ALMA millimeter continuum and line observations in (transition) disks
• A tunnel and a traffic jam: How transition disks maintain a detectable warm dust component despite the presence of a large planet-carved gap
• Spatially resolved PAH emission in the inner disks of Herbig Ae/Be stars
• 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
• Probing CO and N${}_2$ Snow Surfaces in Protoplanetary Disks with N${}_2$H${}^{+}$ Emission
• Annular substructures in the transition disks around LkCa 15 and J1610
• The dispersal of protoplanetary discs. II: Photoevaporation models with observationally derived irradiating spectra
• An ALMA Survey of H${}_2$CO in Protoplanetary Disks
• Modeling the gas-phase chemistry of the transitional disk around HD 141569A
• The chemical inventory of the planet-hosting disk PDS 70
• A Keplerian Disk around the Herbig Ae star HD169142
• The magnetic propeller accretion regime of LkCa 15
• The TW Hya Rosetta Stone Project III: Resolving the Gaseous Thermal Profile of the Disk
• DIGIT survey of far-infrared lines from protoplanetary discs: II. CO
• Rossby wave instability does not require sharp resistivity gradients
• The architecture of the LkCa 15 transitional disk revealed by high-contrast imaging
• Chemically tracing the water snowline in protoplanetary disks with HCO${}^{+}$
• Observability of Forming Planets and their Circumplanetary Disks I. -- Parameter Study for ALMA
• A highly non-Keplerian protoplanetary disc: Spiral structure in the gas disc of CQ Tau
• Variability of Disk Emission in Pre-Main Sequence and Related Stars. III. Exploring Structural Changes in the Pre-transitional Disk in HD 169142
• Probing midplane CO abundance and gas temperature with DCO${}^{+}$ in the protoplanetary disk around HD 169142
• Probing the 2D temperature structure of protoplanetary disks with Herschel observations of high-J CO lines
• Interpreting high spatial resolution line observations of planet-forming disks with gaps and rings -- The case of HD 163296
• Long lived dust rings around HD169142
• Probing the radial temperature structure of protoplanetary disks with Herschel/HIFI
• The TW Hya Rosetta Stone Project II: Spatially resolved emission of formaldehyde hints at low-temperature gas-phase formation
• Dust entrainment in photoevaporative winds: The impact of X-rays
• Chemical Evolution in a Protoplanetary Disk within Planet Carved Gaps and Dust Rings
• Near-Infrared Imaging Polarimetry of LkCa 15: A Possible Warped Inner Disk
• Quantitative polarimetry of the disk around HD 169142
• Variable warm dust around the Herbig Ae star HD~169142: Birth of a ring?

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• Directly tracing the vertical stratification of molecules in protoplanetary disks
• Transition disks: the observational revolution from SEDs to imaging
• Kinematics and brightness temperatures of transition discs -- A survey of gas substructures as seen with ALMA
• ALMA Detection of Dust Trapping around Lagrangian Points in the LkCa 15 Disk
• Tracing snowlines and C/O ratio in a planet-hosting disk: ALMA molecular line observations towards the HD169142 disk
• SO and SiS Emission Tracing an Embedded Planet and Compact ${}^{12}$CO and ${}^{13}$CO Counterparts in the HD 169142 Disk
• Mapping Protoplanetary Disk Vertical Structure with CO Isotopologue Line Emission
• exoALMA V: Gaseous Emission Surfaces and Temperature Structures
• Investigating the asymmetric chemistry in the disk around the young star HD 142527
• When, where, and how many planets end up in first-order resonances?
• Constraining the gas distribution in the PDS 70 disk as a method to assess the effect of planet-disk interactions
• The edge-on protoplanetary disk HH 48 NE I. Modeling the geometry and stellar parameters
• Vertically extended and asymmetric CN emission in the Elias 2-27 protoplanetary 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
• Disentangling protoplanetary disk gas mass and carbon depletion through combined atomic and molecular tracers
• Planet formation in the PDS 70 system: Constraining the atmospheric chemistry of PDS 70b and c
• A dichotomy in group II Herbig disks: ALMA gas disk height measurements show both shadowed large vertically extended disks and compact flat disks
• Vertical CO surfaces as a probe for protoplanetary disk mass and carbon depletion
• On the origin of transition disk cavities: Pebble-accreting protoplanets vs Super-Jupiters
• Constraints on the gas-phase C/O ratio of DR Tau's outer disk from CS, SO, and C${}_2$H observations
• Water vapor emission at the warm cavity wall of the HD 100546 disk as revealed by ALMA
• Zooming into the water snowline: high resolution water observations of the HL Tau disk
• Gravito-turbulent bi-fluid protoplanetary discs: 1. An analytical perspective to stratification
• exoALMA XXIII. Estimating Disk and Planet Properties from Dust Morphologies with DBNets2.0
• Observational evidence for a possible link between PAH emission and dust trap locations in protoplanetary disks
• Protoplanetary Disk Chemistry