Snow-lines can be thermally unstable

Abstract

Volatile species in protoplanetary discs can undergo a phase change from vapour to solid. These "snow-lines" can play vital roles in planet formation at all scales, from dust coagulation to planetary migration. In the outer regions of protoplanetary discs, the temperature profile is set by the absorption of reprocessed stellar light by the solids. Further, the temperature profile sets the distribution of solids through sublimation and condensation at various snow-lines. Hence the snow-line position depends on the temperature profile and vice-versa. We show that this coupling can be thermally unstable, such that a patch of the disc at a snow-line will produce either run-away sublimation or condensation. This thermal instability arises at moderate optical depths, where heating by absorption of reprocessed stellar light from the disc's atmosphere is optically thick, yet cooling is optically thin. Since volatiles in the solid phase drift much faster than volatiles in the vapour phase, this thermal instability results in a limit-cycle. The snow-line progressively moves in, condensing volatiles, before receding, as the volatiles sublimate. Using numerical simulations, we study the evolution of the CO snow-line. We find the CO snow-line is thermally unstable under typical disc conditions and evolves inwards from $\sim 50$ to $\sim 30$~AU on timescales from 1,000-10,000 years. The CO snow-line spends between $\sim 10\%-50\%$ of its time at smaller separations, where the exact value is sensitive to the total opacity and turbulent viscosity. The evolving snow-line also creates ring-like structures in the solid distribution interior to the snow-line. Multiple ring-like structures created by moving snow-lines could potentially explain the sub-structures seen in many {\it ALMA} images.

arXiv commentAccepted for publication in MNRAS

References in corpus (56)

• Spectral Energy Distributions of T Tauri Stars With Passive Circumstellar Disks
• First Results from High Angular Resolution ALMA Observations Toward the HL Tau Region
• The Disk Substructures at High Angular Resolution Project (DSHARP): I. Motivation, Sample, Calibration, and Overview
• The effects of snowlines on C/O in planetary atmospheres
• The disc instability model of dwarf-novae and low-mass X-ray binary transients
• Passive irradiated circumstellar disks with an inner hole
• Coagulation, fragmentation and radial motion of solid particles in protoplanetary disks
• Gas- and dust evolution in protoplanetary disks
• Accretion Disks around Young Objects. I. The Detailed Vertical Structure
• Accretion Disks Around Young Objects. III. Grain Growth
• Wind-driven Accretion in Protoplanetary Disks. I: Suppression of the Magnetorotational Instability and Launching of the Magnetocentrifugal Wind
• The Disk Substructures at High Angular Resolution Project (DSHARP): II. Characteristics of Annular Substructures
• Radial Flow of Dust Particles in Accretion Disks
• Water, O2 and Ice in Molecular Clouds
• The Disk Substructures at High Angular Resolution Project (DSHARP): VII. The Planet-Disk Interactions Interpretation
• An Old Disk That Can Still Form a Planetary System
• Evidence of fast pebble growth near condensation fronts in the HL Tau protoplanetary disk
• Episodic accretion in magnetically layered protoplanetary discs
• Imaging of the CO Snow Line in a Solar Nebula Analog
• Sintering-induced Dust Ring Formation in Protoplanetary Disks: Application to the HL Tau Disk
• Spectral Energy Distributions of T Tauri and Herbig Ae Disks: Grain Mineralogy, Parameter Dependences, and Comparison with ISO LWS Observations
• Global simulations of protoplanetary disks with ohmic resistivity and ambipolar diffusion
• Towards Chemical Constraints on Hot Jupiter Migration
• A Parametric Modeling Approach to Measuring the Gas Masses of Circumstellar Disks
• Grain Retention and Formation of Planetesimals near the Snow Line in MRI-driven Turbulent Protoplanetary Disks
• Chemical enrichment of giant planets and discs due to pebble drift
• Material enhancement in protoplanetary nebulae by particle drift through evaporation fronts
• Magneto-thermal Disk Wind from Protoplanetary Disks
• Mass measurements in protoplanetary disks from hydrogen deuteride
• The thermal structure and the location of the snow line in the protosolar nebula: axisymmetric models with full 3-D radiative transfer
• ALMA continuum observations of the protoplanetary disk AS 209. Evidence of multiple gaps opened by a single planet
• Stellar irradiated discs and implications on migration of embedded planets I: equilibrium discs
• On the Evolution of the Snow Line in Protoplanetary Discs
• Protoplanetary disk rings and gaps across ages and luminosities
• Long-term Evolution of Protostellar and Protoplanetary Disks. I. Outbursts
• Planet-forming material in a protoplanetary disc: the interplay between chemical evolution and pebble drift
• Transport of CO in Protoplanetary Disks: Consequences of Pebble Formation, Settling, and Radial Drift
• Can grain growth explain transition disks?
• C/O and Snowline Locations in Protoplanetary Disks: The Effect of Radial Drift and Viscous Gas Accretion
• Unlocking CO Depletion in Protoplanetary Disks I. The Warm Molecular Layer
• Fast and accurate frequency-dependent radiation transport for hydrodynamics simulations in massive star formation
• The Gravo-Magneto Limit Cycle in Accretion Disks
• Redistribution of CO at the Location of the CO Ice Line in evolving Gas and Dust Disks
• Probing CO and N${}_2$ Snow Surfaces in Protoplanetary Disks with N${}_2$H${}^{+}$ Emission
• The determination of protoplanetary disk masses
• Fingerprints of giant planets in the composition of solar twins
• Mass constraints for 15 protoplanetary disks from HD 1-0
• Dust properties across the CO snowline in the HD 163296 disk from ALMA and VLA observations
• Dwarf Nova Outbursts with Magnetorotational Turbulence
• Using Ice and Dust Lines to Constrain the Surface Densities of Protoplanetary Disks
• Propagation of the Gravo-Magneto Disc Instability
• Accreting planets as dust dams in `transition' discs
• On the evolution of the CO snow line in protoplanetary disks
• Structure of Passive Circumstellar Disks: Beyond the Two-Temperature Approximation
• An analysis of two-layer models for circumstellar disks
• Importance of thermal diffusion in the gravo-magnetic limit cycle

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• Global Three-Dimensional Simulations of Outer Protoplanetary Disks with Ambipolar Diffusion
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• Interpreting high spatial resolution line observations of planet-forming disks with gaps and rings -- The case of HD 163296
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