Rapid Evolution of Volatile CO from the Protostellar Disk Stage to the Protoplanetary Disk Stage

Abstract

Recent observations show that the CO gas abundance, relative to H${}_2$, in many 1-10 Myr old protoplanetary disks may be heavily depleted, by a factor of 10-100 compared to the canonical interstellar medium value of 10${}^{-4}$. When and how this depletion happens can significantly affect compositions of planetesimals and atmospheres of giant planets. It is therefore important to constrain if the depletion occurs already at the earliest protostellar disk stage. Here we present spatially resolved observations of C${}^{18}$O, C${}^{17}$O, and ${}^{13}$C${}^{18}$O $J$=2-1 lines in three protostellar disks. We show that the C${}^{18}$O line emits from both the disk and the inner envelope, while C${}^{17}$O and ${}^{13}$C${}^{18}$O lines are consistent with a disk origin. The line ratios indicate that both C${}^{18}$O and C${}^{17}$O lines are optically thick in the disk region, and only ${}^{13}$C${}^{18}$O line is optically thin. The line profiles of the ${}^{13}$C${}^{18}$O emissions are best reproduced by Keplerian gaseous disks at similar sizes as their mm-continuum emissions, suggesting small radial separations between the gas and mm-sized grains in these disks, in contrast to the large separation commonly seen in protoplanetary disks. Assuming a gas-to-dust ratio of 100, we find that the CO gas abundances in these protostellar disks are consistent with the ISM abundance within a factor of 2, nearly one order of magnitude higher than the average value of 1-10 Myr old disks. These results suggest that there is a fast, $\sim$1 Myr, evolution of the abundance of CO gas from the protostellar disk stage to the protoplanetary disk stage.

arXiv comment10 pages, 3 figures, 2 tables. Accepted for publication in ApJL

References in corpus (52)

• Astropy: A Community Python Package for Astronomy
• Protoplanetary Disks and Their Evolution
• First Results from High Angular Resolution ALMA Observations Toward the HL Tau Region
• Interpreting Spectral Energy Distributions from Young Stellar Objects. II. Fitting observed SEDs using a large grid of pre-computed models
• ALMA Survey of Lupus Protoplanetary Disks I: Dust and Gas Masses
• Dust and Gas in the disc of HL Tauri: Surface density, dust settling, and dust-to-gas ratio
• ALMA Survey of Lupus Protoplanetary Disks II: Gas Disk Radii
• Spiral Density Waves in a Young Protoplanetary Disk
• Evidence of fast pebble growth near condensation fronts in the HL Tau protoplanetary disk
• The ancient heritage of water ice in the solar system
• The TW Hya Disk at 870 microns: Comparison of CO and Dust Radial Structures
• A Parametric Modeling Approach to Measuring the Gas Masses of Circumstellar Disks
• Warm Molecular Layers in Protoplanetary Disks
• Constraining the X-ray and Cosmic Ray Ionization Chemistry of the TW Hya Protoplanetary Disk: Evidence for a Sub-interstellar Cosmic Ray Rate
• The Radial Distribution of H2 and CO in TW Hya as Revealed by Resolved ALMA Observations of CO Isotopologues
• Evidence for a correlation between mass accretion rates onto young stars and the mass of their protoplanetary disks
• Volatile carbon locking and release in protoplanetary disks. A study of TW Hya and HD 100546
• A Significantly Low CO Abundance Toward the TW Hya Protoplanetary Disk: A Path to Active Carbon Chemistry?
• Mass measurements in protoplanetary disks from hydrogen deuteride
• Setting the volatile composition of (exo)planet-building material. Does chemical evolution in disk midplanes matter?
• Molecular abundances and C/O ratios in chemically evolving planet-forming disk midplanes
• On the Outer Edges of Protoplanetary Dust Disks
• Determining protoplanetary disk gas masses from CO isotopologues line observations
• Mass inventory of the giant-planet formation zone in a solar nebula analog
• Protostars: Forges of cosmic rays?
• Transport of CO in Protoplanetary Disks: Consequences of Pebble Formation, Settling, and Radial Drift
• An ALMA Survey of CO isotopologue emission from Protoplanetary Disks in Chamaeleon I
• CO destruction in protoplanetary disk midplanes: inside versus outside the CO snow surface
• ALMA Observations of the Transition from Infall Motion to Keplerian Rotation around the Late-phase Protostar TMC-1A
• Unlocking CO Depletion in Protoplanetary Disks I. The Warm Molecular Layer
• Gas vs dust sizes of protoplanetary disks: effects of dust evolution
• Millimeter imaging of MWC 758: probing the disk structure and kinematics
• Systematic Variations of CO Gas Abundance with Radius in Gas-rich Protoplanetary Disks
• Evidence for the start of planet formation in a young circumstellar disk
• High-J CO survey of low-mass protostars observed with Herschel-HIFI
• Volatile snowlines in embedded disks around low-mass protostars
• Exploring the Origins of Carbon in Terrestrial Worlds
• Chemistry in Protoplanetary Disks: the gas-phase CO/H2 ratio and the Carbon reservoir
• HD far infrared emission as a measure of protoplanetary disk mass
• Unveiling the physical conditions of the youngest disks: A warm embedded disk in L1527
• The First Detection of 13C17O in a Protoplanetary Disk: a Robust Tracer of Disk Gas Mass
• New Constraints From Dust Lines On The Surface Densities Of Protoplanetary Disks
• Are protoplanetary disks born with vortices? -- Rossby wave instability driven by protostellar infall
• Probing Planet Forming Zones with Rare CO Isotopologues
• 13C17O suggests gravitational instability in the HL Tau disc
• Probing the CO and methanol snow lines in young protostars. Results from the CALYPSO IRAM-PdBI survey
• Turbulent-diffusion Mediated CO Depletion in Weakly Turbulent Protoplanetary disks
• The ALMA Early Science view of FUor/EXor objects. I. Through the looking-glass of V2775 Ori
• Unlocking CO Depletion in Protoplanetary Disks II. Primordial C/H Predictions Inside the CO Snowline
• 1000 AU Exterior Arcs Connected to the Protoplanetary Disk around HL Tau
• Chemistry of a newly detected circumbinary disk in Ophiuchus
• Exploring the Grain Properties in the Disk of HL Tau with an Evolutionary Model

Cited by in corpus (45)

• Astrochemistry and compositions of planetary systems
• Molecules with ALMA at Planet-forming Scales (MAPS) V: CO gas distributions
• CO Depletion in Protoplanetary Disks: A Unified Picture Combining Physical Sequestration and Chemical Processing
• Molecules with ALMA at Planet-forming Scales (MAPS). VII. Sub-stellar O/H and C/H and super-stellar C/O in planet feeding gas
• The TW Hya Rosetta Stone Project III: Resolving the Gaseous Thermal Profile of the Disk
• On the secular evolution of the ratio between gas and dust radii in protoplanetary discs
• An evolutionary study of volatile chemistry in protoplanetary disks
• ALMA chemical survey of disk-outflow sources in Taurus (ALMA-DOT) V: Sample, overview, and demography of disk molecular emission
• Large-scale CO spiral arms and complex kinematics associated with the T Tauri star RU Lup
• X-ray induced chemistry of water and related molecules in low-mass protostellar envelopes
• The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): I. Program Overview and Summary of First Results
• Chemical Feedbacks of Pebble Growth: Impacts on CO depletion and C/O ratios
• Destruction of refractory carbon grains drives the final stage of proto-planetary disk chemistry
• Tracing pebble drift and trapping using radial carbon depletion profiles in protoplanetary disks
• Depletion of gaseous CO in protoplanetary disks by surface-energy-regulated ice formation
• Inferring (Sub)millimeter Dust Opacities and Temperature Structure in Edge-on Protostellar Disks From Resolved Multi-Wavelength Continuum Observations: The Case of the HH 212 Disk
• Effect of MHD wind-driven disk evolution on the observed sizes of protoplanetary disks
• The Anatomy of an Unusual Edge-on Protoplanetary Disk. II. Gas temperature and a warm outer region
• ALMA Band 6 high-resolution observations of the transitional disk around SY Cha
• If you like C/O variations, you should have put a ring on it
• On the stickiness of CO${}_2$ and H${}_2$O ice particles
• Resolved molecular line observations reveal an inherited molecular layer in the young disk around TMC1A
• Measuring elemental abundance ratios in protoplanetary disks at millimeter wavelengths
• Different degrees of nitrogen and carbon depletion in the warm molecular layers of protoplanetary disks
• The impact of pre-main sequence stellar evolution on midplane snowline locations and C/O in planet forming discs
• Observational signatures of eccentric Jupiters inside gas cavities in protoplanetary discs
• The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): IV. Dust and Gas Disk Properties in the Upper Scorpius Star-forming Region
• Disentangling protoplanetary disk gas mass and carbon depletion through combined atomic and molecular tracers
• ALMA chemical survey of disk-outflow sources in Taurus (ALMA-DOT) III: The interplay between gas and dust in the protoplanetary disk of DG Tau
• PDRs4All. X. ALMA and JWST detection of neutral carbon in the externally irradiated disk d203-506: Undepleted gas-phase carbon
• The Molecular Composition of Shadowed Protosolar Disk Midplanes beyond the Water Snowline
• Testing protoplanetary disc evolution with CO fluxes. A proof of concept in Lupus and Upper Sco
• A potential site for wide-orbit giant planet formation in the IM Lup disk
• Chemical transformation of CO in evolving protoplanetary discs across stellar masses: a route to C-rich inner regions
• Vertical CO surfaces as a probe for protoplanetary disk mass and carbon depletion
• Chemical evolution in planet-forming regions with growing grains
• Global Modeling of Nebulae With Particle Growth, Drift, and Evaporation Fronts. III. Redistribution of Refractories and Volatiles
• Constraints on the gas-phase C/O ratio of DR Tau's outer disk from CS, SO, and C${}_2$H observations
• Constraining the Stellar Masses and Origin of the Protostellar VLA 1623 System
• A CO-to-H${}_2$ ratio of $\approx 10^{-5}$ towards the Herbig Ae star HK Ori
• SHAMPOO: A stochastic model for tracking dust particles under the influence of non-local disk processes
• Molecules with ALMA at Planet-forming Scales (MAPS). XV. Tracing protoplanetary disk structure within 20 au
• Protostellar disc structure and dynamics during star formation from cloud-scale initial conditions
• High CO/H2 ratios supports an exocometary origin for a CO-rich debris disk
• Which molecule traces what: chemical diagnostics of protostellar sources