On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability
High-resolution submillimeter observations of protoplanetary disks with ALMA have revealed that dust rings are common in large, bright disks. The leading explanation for these structures is dust trapping in a local gas pressure maximum, caused by an embedded planet or other dynamical process. Indepe...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/2041-8213/acc17b |
| _version_ | 1797701917323821056 |
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| author | Eonho Chang Andrew N. Youdin Leonardo Krapp |
| author_facet | Eonho Chang Andrew N. Youdin Leonardo Krapp |
| author_sort | Eonho Chang |
| collection | DOAJ |
| description | High-resolution submillimeter observations of protoplanetary disks with ALMA have revealed that dust rings are common in large, bright disks. The leading explanation for these structures is dust trapping in a local gas pressure maximum, caused by an embedded planet or other dynamical process. Independent of origin, such dust traps should be stable for many orbits to collect significant dust. However, ringlike perturbations in gas disks are also known to trigger the Rossby wave instability (RWI). We investigate whether axisymmetric pressure bumps can simultaneously trap dust and remain stable to the RWI. The answer depends on the thermodynamic properties of pressure bumps. For isothermal bumps, dust traps are RWI stable for widths from ∼1 to several gas scale heights. Adiabatic dust traps are stable over a smaller range of widths. For temperature bumps with no surface density component, however, all dust traps tend to be unstable. Smaller values of disk aspect ratio allow stable dust trapping at lower bump amplitudes and over a larger range of widths. We also report a new approximate criterion for RWI. Instability occurs when the radial oscillation frequency is ≲75% of the Keplerian frequency, which differs from the well-known Lovelace necessary (but not sufficient) criterion for instability. Our results can guide ALMA observations of molecular gas by constraining the resolution and sensitivity needed to identify the pressure bumps thought to be responsible for dust rings. |
| first_indexed | 2024-03-12T04:42:34Z |
| format | Article |
| id | doaj.art-08cc8973632b482da3bdd831ec89e75d |
| institution | Directory Open Access Journal |
| issn | 2041-8205 |
| language | English |
| last_indexed | 2024-03-12T04:42:34Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal Letters |
| spelling | doaj.art-08cc8973632b482da3bdd831ec89e75d2023-09-03T09:30:39ZengIOP PublishingThe Astrophysical Journal Letters2041-82052023-01-019461L110.3847/2041-8213/acc17bOn the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave InstabilityEonho Chang0https://orcid.org/0000-0003-4703-2053Andrew N. Youdin1https://orcid.org/0000-0002-3644-8726Leonardo Krapp2https://orcid.org/0000-0001-7671-9992Graduate Interdisciplinary Program in Applied Mathematics, University of Arizona , Tucson, AZ 85721, USA ; eonhochang@arizona.edu; Department of Astronomy and Steward Observatory, University of Arizona , Tucson, AZ 85721, USADepartment of Astronomy and Steward Observatory, University of Arizona , Tucson, AZ 85721, USA; The Lunar and Planetary Laboratory, University of Arizona, Tucson , AZ 85721, USADepartment of Astronomy and Steward Observatory, University of Arizona , Tucson, AZ 85721, USAHigh-resolution submillimeter observations of protoplanetary disks with ALMA have revealed that dust rings are common in large, bright disks. The leading explanation for these structures is dust trapping in a local gas pressure maximum, caused by an embedded planet or other dynamical process. Independent of origin, such dust traps should be stable for many orbits to collect significant dust. However, ringlike perturbations in gas disks are also known to trigger the Rossby wave instability (RWI). We investigate whether axisymmetric pressure bumps can simultaneously trap dust and remain stable to the RWI. The answer depends on the thermodynamic properties of pressure bumps. For isothermal bumps, dust traps are RWI stable for widths from ∼1 to several gas scale heights. Adiabatic dust traps are stable over a smaller range of widths. For temperature bumps with no surface density component, however, all dust traps tend to be unstable. Smaller values of disk aspect ratio allow stable dust trapping at lower bump amplitudes and over a larger range of widths. We also report a new approximate criterion for RWI. Instability occurs when the radial oscillation frequency is ≲75% of the Keplerian frequency, which differs from the well-known Lovelace necessary (but not sufficient) criterion for instability. Our results can guide ALMA observations of molecular gas by constraining the resolution and sensitivity needed to identify the pressure bumps thought to be responsible for dust rings.https://doi.org/10.3847/2041-8213/acc17bAstrophysical fluid dynamicsCircumstellar dustPlanet formationProtoplanetary disksSubmillimeter astronomyHydrodynamics |
| spellingShingle | Eonho Chang Andrew N. Youdin Leonardo Krapp On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability The Astrophysical Journal Letters Astrophysical fluid dynamics Circumstellar dust Planet formation Protoplanetary disks Submillimeter astronomy Hydrodynamics |
| title | On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability |
| title_full | On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability |
| title_fullStr | On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability |
| title_full_unstemmed | On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability |
| title_short | On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability |
| title_sort | on the origin of dust structures in protoplanetary disks constraints from the rossby wave instability |
| topic | Astrophysical fluid dynamics Circumstellar dust Planet formation Protoplanetary disks Submillimeter astronomy Hydrodynamics |
| url | https://doi.org/10.3847/2041-8213/acc17b |
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