Stirring in massive, young debris discs from spatially resolved Herschel images

Abstract

A significant fraction of main-sequence stars are encircled by dusty debris discs, where the short-lived dust particles are replenished through collisions between planetesimals. Most destructive collisions occur when the orbits of smaller bodies are dynamically stirred up, either by the gravitational effect of locally formed Pluto-sized planetesimals (self-stirring scenario), or via secular perturbation caused by an inner giant planet (planetary stirring). The relative importance of these scenarios in debris systems is unknown. Here we present new Herschel Space Observatory imagery of 11 discs selected from the most massive and extended known debris systems. All discs were found to be extended at far-infrared wavelengths, five of them being resolved for the first time. We evaluated the feasibility of the self-stirring scenario by comparing the measured disc sizes with the predictions of the model calculated for the ages of our targets. We concluded that the self-stirring explanation works for seven discs. However, in four cases, the predicted pace of outward propagation of the stirring front, assuming reasonable initial disc masses, was far too low to explain the radial extent of the cold dust. Therefore, for HD 9672, HD 16743, HD 21997, and HD 95086, another explanation is needed. We performed a similar analysis for ß Pic and HR 8799, reaching the same conclusion. We argue that planetary stirring is a promising possibility to explain the disk properties in these systems. In HR 8799 and HD 95086 we may already know the potential perturber, since their known outer giant planets could be responsible for the stirring process. Our study demonstrates that among the largest and most massive debris discs self-stirring may not be the only active scenario, and potentially planetary stirring is responsible for destructive collisions and debris dust production in a number of systems.

Accepted for publication in MNRAS, 22 pages, 7 figures, 6 tables (abstract abridged due to arXiv requirements)

References in corpus (23)

• Direct Imaging of Multiple Planets Orbiting the Star HR 8799
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey
• Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Southern Sample
• Towards planetesimals: dense chondrule clumps in the protoplanetary nebula
• On the age of the $\beta$ Pictoris moving group
• Transience of hot dust around sun-like stars
• Variations on Debris Disks: Icy Planet Formation at 30-150 AU for 1-3 Solar Mass Main Sequence Stars
• Molecular Gas Clumps from the Destruction of Icy Bodies in the $\beta$ Pictoris Debris Disk
• Nearby debris disk systems with high fractional luminosity reconsidered
• Long-Term Collisional Evolution of Debris Disks
• Resolved Debris Discs Around A Stars in the Herschel DEBRIS Survey
• Parameters of Herbig Ae/Be and Vega-type stars
• Do Two Temperature Debris Disks Have Multiple Belts?
• Disk Radii and Grain Sizes in Herschel-Resolved Debris Disks
• The Dust Properties of Eight Debris Disk Candidates as Determined by Submillimeter Photometry
• Revealing Asymmetries in the HD 181327 Debris Disk: A Recent Massive Collision or ISM Warping
• Sizes of protoplanetary discs after star-disc encounters
• Long-wavelength observations of debris discs around sun-like stars
• Formation of Narrow Dust Rings in Circumstellar Debris Disks
• High-Resolution Imaging of the Dust Disk around 49 Ceti
• Porous dust grains in debris disks
• The Exceptionally Large Debris Disk around γOphiuchi

Cited by in corpus (26)

• SONS: The JCMT legacy survey of debris discs in the submillimetre
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• Solution to the debris disc mass problem: planetesimals are born small?
• Discovery of a Substellar Companion to the Nearby Debris Disk Host HR 2562
• Planet populations inferred from debris discs: insights from 178 debris systems in the ISPY, LEECH and LIStEN planet-hunting surveys
• Gas and dust around A-type stars at tens of Myr:signatures of cometary breakup
• A search for a 5th planet around HR 8799 using the star-hopping RDI technique at VLT/SPHERE
• First scattered-light images of the gas-rich debris disk around 49 Ceti
• New debris disks in nearby young moving groups
• Effects of inclined star-disk encounter on protoplanetary disk size
• Primordial or Secondary? Testing models of debris disk gas with ALMA
• Herschel Observations of Dusty Debris Disks
• What Sets the Radial Locations of Warm Debris Disks?
• Stirred but not shaken: a multi-wavelength view of HD 16743's debris disc
• The ALMA survey to Resolve exoKuiper belt Substructures (ARKS) II. The radial structure of debris discs
• RVSPY -- Radial Velocity Survey for Planets around Young Stars. Target characterization and high-cadence survey
• High-contrast observations of brown dwarf companion HR 2562 B with the vector Apodizing Phase Plate coronagraph
• The big sibling of AU Mic: a cold dust-rich debris disk around CP-72 2713 in the $\beta$ Pic moving group
• Flybys in debris disk systems with Gaia eDR3
• A multi-wavelength study of the debris disc around 49 Cet
• A Mixed Stirring Mechanism for Debris Discs with Giant and Dwarf Planetary Perturbations
• An unusually large gaseous transit in a debris disc
• Multi-wavelength, spatially resolved modelling of HD 48682's debris disc
• Radial velocity analysis of stars with debris discs
• Discovery of carbon monoxide emission from five debris disks around young A-type stars
• Testing the Impact of Planet-stirring, Self-stirring, and Mixed-stirring on Debris Disc Architecture: A Case Study of HD 16743