The observational impact of dust trapping in self-gravitating discs

Abstract

We present a 3D semi-analytic model of self-gravitating discs, and include a prescription for dust trapping in the disc spiral arms. Using Monte-Carlo radiative transfer we produce synthetic ALMA observations of these discs. In doing so we demonstrate that our model is capable of producing observational predictions, and able to model real image data of potentially self-gravitating discs. For a disc to generate spiral structure that would be observable with ALMA requires that the disc's dust mass budget is dominated by millimetre and centimetre-sized grains. Discs in which grains have grown to the grain fragmentation threshold may satisfy this criterion, thus we predict that signatures of gravitational instability may be detectable in discs of lower mass than has previously been suggested. For example, we find that discs with disc-to-star mass ratios as low as $0.10$ are capable of driving observable spiral arms. Substructure becomes challenging to detect in discs where no grain growth has occurred or in which grain growth has proceeded well beyond the grain fragmentation threshold. We demonstrate how we can use our model to retrieve information about dust trapping and grain growth through multi-wavelength observations of discs, and using estimates of the opacity spectral index. Applying our disc model to the Elias 27, WaOph 6 and IM Lup systems we find gravitational instability to be a plausible explanation for the observed substructure in all 3 discs, if sufficient grain growth has indeed occurred.

arXiv comment19 pages, 21 figures, accepted for publication in MNRAS

References in corpus (57)

• Gaia Data Release 2. Summary of the contents and survey properties
• Protoplanetary Disks and Their Evolution
• Streaming Instabilities in Protoplanetary Disks
• The Disk Substructures at High Angular Resolution Project (DSHARP): I. Motivation, Sample, Calibration, and Overview
• Nonlinear Outcome of Gravitational Instability in Cooling, Gaseous Disks
• A simple model for the evolution of the dust population in protoplanetary disks
• Coagulation, fragmentation and radial motion of solid particles in protoplanetary disks
• Dust coagulation in protoplanetary disks: a rapid depletion of small grains
• Gas- and dust evolution in protoplanetary disks
• The outcome of protoplanetary dust growth: pebbles, boulders, or planetesimals? II. Introducing the bouncing barrier
• The outcome of protoplanetary dust growth: pebbles, boulders, or planetesimals? I. Mapping the zoo of laboratory collision experiments
• On the Submillimeter Opacity of Protoplanetary Disks
• The Disk Substructures at High Angular Resolution Project (DSHARP): II. Characteristics of Annular Substructures
• Phantom: A smoothed particle hydrodynamics and magnetohydrodynamics code for astrophysics
• Dust Properties of Protoplanetary Disks in the Taurus-Auriga Star Forming Region from Millimeter Wavelengths
• Disks ARound TTauri Stars with Sphere (DARTTS-S) I: Sphere / IRDIS Polarimetric Imaging of 8 prominent TTauri Disks
• The locality of transport in self-gravitating accretion discs
• Investigating fragmentation conditions in self-gravitating accretion discs
• Spiral Density Waves in a Young Protoplanetary Disk
• On the Dynamical Foundations of Alpha Disks
• Dust size distributions in coagulation/fragmentation equilibrium: Numerical solutions and analytical fits
• Observational Signatures of Planets in Protoplanetary Disks II: Spiral Arms Observed in Scattered Light Imaging Can be Induced by Planets
• Large grains in the disk of CQ Tau
• Pseudo-viscous modeling of self-gravitating discs and the formation of low mass ratio binaries
• Accelerated planetesimal growth in self-gravitating protoplanetary discs
• Characterising the Gravitational Instability in Cooling Accretion Discs
• Dust Evolution in Protoplanetary Disks
• The Coupled Physical Structure of Gas and Dust in the IM Lup Protoplanetary Disk
• The Disk Substructures at High Angular Resolution Project (DSHARP): III. Spiral Structures in the Millimeter Continuum of the Elias 27, IM Lup, and WaOph 6 Disks
• Radiative transfer and the energy equation in SPH simulations of star formation
• The Disk Substructures at High Angular Resolution Project (DSHARP): IV. Characterizing substructures and interactions in disks around multiple star systems
• Planetesimal formation via fragmentation in self-gravitating protoplanetary discs
• Dusty gas with SPH - I. Algorithm and test suite
• Time-dependent models of the structure and evolution of self-gravitating protoplanetary discs
• Grand Design Spiral Arms in A Young Forming Circumstellar Disk
• Spiral Arms in Gravitationally Unstable Protoplanetary Disks as Imaged in Scattered Light
• 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
• On the origin of the spiral morphology in the Elias 2-27 circumstellar disc
• Dust trapping by spiral arms in gravitationally unstable protostellar discs
• Spiral Arms in Disks: Planets or Gravitational Instability?
• Free Collisions in a Microgravity Many-Particle Experiment III: The Collision Behavior of sub-Millimeter-Sized Dust Aggregates
• A fast and explicit algorithm for simulating the dynamics of small dust grains with smoothed particle hydrodynamics
• The role of disc self-gravity in the formation of protostars and protostellar discs
• Dusty gas with SPH - II. Implicit timestepping and astrophysical drag regimes
• Planet-driven spiral arms in protoplanetary disks: II. Implications
• The Evolution of Protostars: Insights from Ten Years of Infrared Surveys with Spitzer and Herschel
• How to Detect the Signatures of Self-Gravitating Circumstellar Discs with the Atacama Large Millimetre/sub-millimetre Array
• SPH simulations of grain growth in protoplanetary disks
• Is the spiral morphology of the Elias 2-27 circumstellar disc due to gravitational instability?
• Massive discs around low-mass stars
• Directly observing continuum emission from self-gravitating spiral waves
• The temporal requirements of directly observing self-gravitating spiral waves in protoplanetary discs with ALMA
• Size-sorting dust grains in the surface layers of protoplanetary disks
• Fragmentation favoured in discs around higher mass stars
• Multi-wavelength observations of protoplanetary discs as a proxy for the gas disc mass
• A Self-Gravitating Disc Around L1527 IRS?

Cited by in corpus (9)

• Spiral Arms and a Massive Dust Disk with non-Keplerian Kinematics: Possible Evidence for Gravitational Instability in the Disk of Elias 2-27
• A dynamical measurement of the disk mass in Elias 2-27
• Spiral structures in gravito-turbulent gaseous disks
• Direct Formation of Planetary Embryos in Self-Gravitating Disks
• Binary companions triggering fragmentation in self-gravitating discs
• Particle Dynamics in 3D Self-gravitating Disks I: Spirals
• AB Aurigae: Possible evidence of planet formation through the gravitational instability
• Searching for wide-orbit gravitational instability protoplanets with ALMA in the dust continuum
• Constraining protoplanetary disc mass using the GI wiggle