CO Line Emission Surfaces and Vertical Structure in Mid-Inclination Protoplanetary Disks

Abstract

High spatial resolution CO observations of mid-inclination (30-75°) protoplanetary disks offer an opportunity to study the vertical distribution of CO emission and temperature. The asymmetry of line emission relative to the disk major axis allows for a direct mapping of the emission height above the midplane, and for optically-thick, spatially-resolved emission in LTE, the intensity is a measure of the local gas temperature. Our analysis of ALMA archival data yields CO emission surfaces, dynamically-constrained stellar host masses, and disk atmosphere gas temperatures for the disks around: HD 142666, MY Lup, V4046 Sgr, HD 100546, GW Lup, WaOph 6, DoAr 25, Sz 91, CI Tau, and DM Tau. These sources span a wide range in stellar masses (0.50-2.10 M${}_{\odot }$), ages ($\sim$0.3-23 Myr), and CO gas radial emission extents ($\approx$200-1000 au). This sample nearly triples the number of disks with mapped emission surfaces and confirms the wide diversity in line emitting heights ($z/r\approx 0.1$ to $\gtrsim 0.5$) hinted at in previous studies. We compute radial and vertical CO gas temperature distributions for each disk. A few disks show local temperature dips or enhancements, some of which correspond to dust substructures or the proposed locations of embedded planets. Several emission surfaces also show vertical substructures, which all align with rings and gaps in the millimeter dust. Combining our sample with literature sources, we find that CO line emitting heights weakly decline with stellar mass and gas temperature, which, despite large scatter, is consistent with simple scaling relations. We also observe a correlation between CO emission height and disk size, which is due to the flared structure of disks. Overall, CO emission surfaces trace $\approx 2$-$5\times$ gas pressure scale heights (H${}_{\mathrm{g}}$) and could potentially be calibrated as empirical tracers of H${}_{\mathrm{g}}$.

arXiv comment31 pages, 17 figures, accepted for publication in ApJ. Image cubes available at https://zenodo.org/record/6410045

References in corpus (111)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Astropy: A Community Python Package for Astronomy
• emcee: The MCMC Hammer
• The NumPy array: a structure for efficient numerical computation
• Binary companions of evolved stars in APOGEE DR14: Search method and catalog of ~5,000 companions
• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• Spectral Energy Distributions of T Tauri Stars With Passive Circumstellar Disks
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• Protoplanetary Disks and Their Evolution
• The Disk Substructures at High Angular Resolution Project (DSHARP): I. Motivation, Sample, Calibration, and Overview
• Passive irradiated circumstellar disks with an inner hole
• Resolved Images of Large Cavities in Protoplanetary Transition Disks
• Accretion Disks around Young Objects. I. The Detailed Vertical Structure
• Gaps and Rings in an ALMA Survey of Disks in the Taurus Star-forming Region
• The Disk Substructures at High Angular Resolution Project (DSHARP): II. Characteristics of Annular Substructures
• The Disk Substructures at High Angular Resolution Project (DSHARP) VI: Dust trapping in thin-ringed protoplanetary disks
• ALMA Survey of Lupus Protoplanetary Disks II: Gas Disk Radii
• Disks ARound TTauri Stars with Sphere (DARTTS-S) I: Sphere / IRDIS Polarimetric Imaging of 8 prominent TTauri Disks
• On the age of the $\beta$ Pictoris moving group
• Probing the structure of protoplanetary disks: a comparative study of DM Tau, LkCa 15 and MWC 480
• Molecules with ALMA at Planet-forming Scales (MAPS) I: Program Overview and Highlights
• The warm gas atmosphere of the HD 100546 disk seen by Herschel (Evidence of a gas-rich, carbon-poor atmosphere?)
• ALMA unveils rings and gaps in the protoplanetary system HD 169142: signatures of two giant protoplanets
• A lithium depletion boundary age of 21 Myr for the Beta Pictoris moving group
• A Spatially Resolved Vertical Temperature Gradient in the HD 163296 Disk
• A Millimeter Continuum Size-Luminosity Relationship for Protoplanetary Disks
• Meridional flows in the disk around a young star
• Chemical Processes in Protoplanetary Disks
• Direct mapping of the temperature and velocity gradients in discs. Imaging the vertical CO snow line around IM Lupi
• Unveiling the gas and dust disk structure in HD 163296 using ALMA observations
• Chemical evolution of turbulent protoplanetary disks and the Solar nebula
• Gaia DR2 study of Herbig Ae/Be stars
• Observations of edge-on protoplanetary disks with ALMA I. Results from continuum data
• Kinematic detection of a planet carving a gap in a protoplanetary disc
• The Disk Substructures at High Angular Resolution Project (DSHARP) - IX. A high definition study of the HD 163296 planet forming disk
• Measuring turbulent motion in planet-forming disks with ALMA: A detection around DM Tau and non-detections around MWC 480 and V4046 Sgr
• Molecules with ALMA at Planet-forming Scales (MAPS) V: CO gas distributions
• Nine localised deviations from Keplerian rotation in the DSHARP circumstellar disks: Kinematic evidence for protoplanets carving the gaps
• Different dust and gas radial extents in protoplanetary disks: consistent models of grain growth and CO emission
• Direct detection of scattered light gaps in the transitional disk around HD 97048 with VLT/SPHERE
• Meridional circulation of gas into gaps opened by giant planets in three-dimensional low-viscosity disks
• Molecules with ALMA at Planet-forming Scales (MAPS) IV: Emission Surfaces and Vertical Distribution of Molecules
• The complex structure of the disk around HD100546: the inner few astronomical units
• A highly settled disk around Oph 163131
• Chemistry of a protoplanetary disk with grain settling and Lyman alpha radiation
• ALMA hints at the presence of two companions in the disk around HD 100546
• Planet formation signposts: observability of circumplanetary disks via gas kinematics
• The SPHERE view of the planet-forming disk around HD100546
• Masses and Implications for Ages of Low-Mass Pre-Main Sequence Stars in Taurus and Ophiuchus
• A Close-up View of the Young Circumbinary Disk HD 142527
• A cavity and further radial substructures in the disk around HD~97048
• High resolution millimetre imaging of the CI Tau protoplanetary disc - a massive ensemble of protoplanets from 0.1 - 100 au
• Polarized disk emission from Herbig Ae/Be stars observed using Gemini Planet Imager: HD 144432, HD 150193, HD 163296, and HD 169142
• HD100546 Multi-Epoch Scattered-Light Observations
• Kinematic detections of protoplanets: a Doppler-flip in the disk of HD100546
• The masses of young stars: CN as a probe of dynamical masses
• Disks Around T Tauri Stars with SPHERE (DARTTS-S) II: Twenty-one new polarimetric images of young stellar disks
• High-Resolution ALMA Observations of HD100546: Asymmetric Circumstellar Ring, and Circumplanetary Disk Upper Limits
• Observability of planet-disc interactions in CO kinematics
• Evidence For A Vertical Dependence on the Pressure Structure in AS 209
• Empirical Temperature Measurement in Protoplanetary Disks
• Dust modeling of the combined ALMA and SPHERE datasets of HD163296. Is HD163296 really a Meeus group II disk?
• Multiple Carbon monoxide Snow-lines in Disks Sculpted by Radial Drift
• The Nature of Transition Circumstellar Disks II. Southern Molecular Clouds
• Inferring giant planets from ALMA millimeter continuum and line observations in (transition) disks
• Spiral Arms and a Massive Dust Disk with non-Keplerian Kinematics: Possible Evidence for Gravitational Instability in the Disk of Elias 2-27
• First evidence of external disc photoevaporation in a low mass star forming region: the case of IM Lup
• Perturbers: SPHERE detection limits to planetary-mass companions in protoplanetary disks
• 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
• A Disk-based Dynamical Mass Estimate for the Young Binary V4046 Sgr
• The Flying Saucer: Tomography of the thermal and density gas structure of an edge-on protoplanetary disk
• Gas Disk Sizes from CO Line Observations: A Test of Angular Momentum Evolution
• Molecules with ALMA at Planet-forming Scales (MAPS). IX. Distribution and Properties of the Large Organic Molecules HC${}_3$N, CH${}_3$CN, and $c$-C${}_3$H${}_2$
• Long Baseline Observations of the HD100546 Protoplanetary Disk with ALMA
• ALMA chemical survey of disk-outflow sources in Taurus (ALMA-DOT) II: Vertical stratification of CO, CS, CN, H${}_2$CO, and CH${}_3$OH in a Class I disk
• Dynamical Masses of Low Mass Stars in the Taurus and Ophiuchus Star Forming Regions
• ALMA reveals the anatomy of the mm-sized dust and molecular gas in the HD 97048 disk
• The magnetic field and accretion regime of CI Tau
• A dynamical measurement of the disk mass in Elias 2-27
• Resolved images of the protoplanetary disk around HD 100546 with ALMA
• A dusty filament and turbulent CO spirals in HD135344B-SAO206462
• Rings and gaps in protoplanetary disks: planets or snowlines?
• Molecules with ALMA at Planet-forming Scales (MAPS) XI: CN and HCN as Tracers of Photochemistry in Disks
• A ring-like concentration of mm-sized particles in Sz 91
• A Spatially Resolved AU-scale Inner Disk around DM Tau
• Observational Signatures of Tightly Wound Spirals Driven by Buoyancy Resonances in Protoplanetary Disks
• ALMA chemical survey of disk-outflow sources in Taurus (ALMA-DOT) V: Sample, overview, and demography of disk molecular emission
• High-Contrast study of the candidate planets and protoplanetary disk around HD~100546
• Probing the 2D temperature structure of protoplanetary disks with Herschel observations of high-J CO lines
• The shadow of the Flying Saucer: A very low temperature for large dust grains
• Interpreting high spatial resolution line observations of planet-forming disks with gaps and rings -- The case of HD 163296
• Gas inside the 97 au cavity around the transition disk Sz\,91
• ALMA 870 $\mu$m continuum observations of HD 100546. Evidence of a giant planet on a wide orbit
• Observational Signatures of Planets in Protoplanetary Disks: Planet-Induced Line Broadening in Gaps
• Investigating the Relative Gas and Small Dust Grain Surface Heights in Protoplanetary Disks
• Mapping the Planetary Wake in HD 163296 with Kinematics
• The Excitation Conditions of CN in TW Hya
• The Architecture of the V892 Tau System: the Binary and its Circumbinary Disk
• The Anatomy of an Unusual Edge-on Protoplanetary Disk. II. Gas temperature and a warm outer region
• The Flared Gas Structure of the Transitional Disk around Sz 91
• Disk Illumination and Jet Variability of the Herbig Ae Star HD 163296 Using Multi-Epoch HST/STIS Optical, Near-IR, and Radio Imagery and Spectroscopy
• A Three Dimensional View of Gomez's Hamburger
• Dynamical Masses and Stellar Evolutionary Model Predictions of M-Stars
• The TW Hya Rosetta Stone Project I: Radial and vertical distributions of DCN and DCO+
• High resolution observations of molecular emission lines toward the CI Tau proto-planetary disc: planet-carved gaps or shadowing?
• Mapping of shadows cast on a protoplanetary disk by a close binary system
• Tracing Molecular Stratification within an Edge-on Protoplanetary Disk
• NaCo polarimetric observations of Sz 91 transitional disk: a remarkable case of dust filtering
• Constraints on a Putative Planet Sculpting the V4046 Sagittarii Circumbinary Disk
• Very Large Telescope observations of Gomez's Hamburger: Insights into a young protoplanet candidate
• Mapping the 3D Kinematical Structure of the Gas Disk of HD 169142