Strengthening the Case for Asteroidal Accrection: Evidence for Subtle and Diverse Disks at White Dwarfs

Abstract

Spitzer Space Telescope IRAC 3-8 micron and AKARI IRC 2-4 micron photometry are reported for ten white dwarfs with photospheric heavy elements; nine relatively cool stars with photospheric calcium, and one hotter star with a peculiar high carbon abundance. A substantial infrared excess is detected at HE 2221-1630, while modest excess emissions are identified at HE 0106-3253 and HE 0307+0746, implying these latter two stars have relatively narrow (Delta r < 0.1 Rsol) rings of circumstellar dust. A likely 7.9 micron excess is found at PG 1225-079 and may represent, together with G166-58, a sub-class of dust ring with a large inner hole. The existence of attenuated disks at white dwarfs substantiates the connection between their photospheric heavy elements and the accretion of disrupted minor planets, indicating many polluted white dwarfs may harbor orbiting dust, even those lacking an obvious infrared excess.

13 pages, emulateapj, accepted to ApJ

References in corpus (13)

• A gaseous metal disk around a white dwarf
• The Chemical Composition of an Extrasolar Minor Planet
• Pollution of single white dwarfs by accretion of many small asteroids
• Chemical Abundances in the Externally Polluted White Dwarf GD 40: Evidence of a Rocky Extrasolar Minor Planet
• Externally-polluted white dwarfs with dust disks
• Debris Disks Around White Dwarfs: The DAZ Connection
• Six White Dwarfs with Circumstellar Silicates
• The accretion-diffusion scenario for metals in cool white dwarfs
• On the Nature of the Dust in the Debris Disk Around HD69830
• Infrared Emission from the Dusty Disk Orbiting GD 362, An Externally-Polluted White Dwarf
• X-ray and Infrared Observations of Two Externally-Polluted White Dwarfs
• Near-Infrared Constraints on the Presence of Warm Dust at Metal-Rich, Helium Atmosphere White Dwarfs
• IRTF Observations of White Dwarfs with Possible Near-Infrared Excess

Cited by in corpus (88)

• Ancient planetary systems are orbiting a large fraction of white dwarf stars
• The Link Between Planetary Systems, Dusty White Dwarfs, and Metal Polluted White Dwarfs
• Circumstellar Debris and Pollution at White Dwarf Stars
• Dynamical effects of stellar mass loss on a Kuiper-like belt
• Evidence for Water in the Rocky Debris of a Disrupted Extrasolar Minor Planet
• Eccentric Planets and Stellar Evolution as a Cause of Polluted White Dwarfs
• Elemental Compositions of Two Extrasolar Rocky Planetesimals
• Global Models of Runaway Accretion in White Dwarf Debris Disks
• Constraints on the Lifetimes of Disks Resulting from Tidally Destroyed Rocky Planetary Bodies
• Cool DZ white dwarfs II: Compositions and evolution of old remnant planetary systems
• The frequency and infrared brightness of circumstellar discs at white dwarfs
• Runaway accretion of metals from compact debris disks onto white dwarfs
• Metal accretion onto white dwarfs caused by Poynting-Robertson drag on their debris disks
• The WIRED Survey II: Infrared Excesses in the SDSS DR7 White Dwarf Catalog
• Detailed compositional analysis of the heavily polluted DBZ white dwarf SDSS J073842.56+183509.06: A window on planet formation?
• Echoes of a decaying planetary system: the gaseous and dusty disks surrounding three white dwarfs
• Likely detection of water-rich asteroid debris in a metal-polluted white dwarf
• Two Beyond-Primitive Extrasolar Planetesimals
• A Trio of Metal-Rich Dust and Gas Disks Found Orbiting Candidate White Dwarfs with K-Band Excess
• Rocky Extrasolar Planetary Compositions Derived from Externally-Polluted White Dwarfs
• The unbiased frequency of planetary signatures around single and binary white dwarfs using $Spitzer$ and $Hubble$
• Signs of a faint disc population at polluted white dwarfs
• Spitzer Observations of White Dwarfs: the Missing Planetary Debris Around DZ Stars
• Scars of Intense Accretion Episodes at Metal-Rich White Dwarfs
• Possible Signs of Water and Differentiation in a Rocky Exoplanetary Body
• Accretion of a Terrestrial-Like Minor Planet by a White Dwarf
• Compositions of Planetary Debris around Dusty White Dwarfs
• Inner edges of compact debris disks around metal-rich white dwarfs
• Precise Atmospheric Parameters for the Shortest Period Binary White Dwarfs: Gravitational Waves, Metals, and Pulsations
• The Survival of Water within Extrasolar Minor Planets
• Gaseous Material Orbiting the Polluted, Dusty White Dwarf HE1349-2305
• Evolution of Planetary Orbits with Stellar Mass Loss and Tidal Dissipation
• Trace hydrogen in helium atmosphere white dwarfs as a possible signature of water accretion
• Detecting industrial pollution in the atmospheres of earth-like exoplanets
• Evidence for an external origin of heavy elements in hot DA white dwarfs
• The frequency of gaseous debris discs around white dwarfs
• White Dwarf Pollution by Asteroids from Secular Resonances
• The Drop during Less than 300 days of a Dusty White Dwarf's Infrared Luminosity
• A Spitzer Space Telescope Study of the Debris Disks around four SDSS White Dwarfs
• The WIRED Survey I: A Bright IR Excess Due to Dust Around the Heavily Polluted White Dwarf GALEX J193156.8+011745
• The scattering of small bodies in planetary systems: constraints on the possible orbits of cometary material
• The Magnetic and Metallic Degenerate G77-50
• Infrared observations of white dwarfs and the implications for the accretion of dusty planetary material
• Cool DZ white dwarfs in the SDSS
• The WIRED Survey. IV. New Dust Disks from the McCook & Sion White Dwarf Catalog
• Transient outburst events from tidally disrupted asteroids near white dwarfs
• Detecting bio-markers in habitable-zone earths transiting white dwarfs
• Detection of Weak Circumstellar Gas around the DAZ White Dwarf WD 1124-293: Evidence for the Accretion of Multiple Asteroids
• Global modeling of radiatively driven accretion of metals from compact debris disks onto the white dwarfs
• Solar Abundances of Rock Forming Elements, Extreme Oxygen and Hydrogen in a Young Polluted White Dwarf
• Infrared Excesses around Bright White Dwarfs from Gaia and unWISE I
• Pressure shifts and abundance gradients in the atmosphere of the DAZ white dwarf GALEX J193156.8+011745
• The puzzling source IGR J17361-4441 in NGC 6388: a possible planetary tidal disruption event
• The dust never settles: collisional production of gas and dust in evolved planetary systems
• Evidence for an Anhydrous Carbonaceous Extrasolar Minor Planet
• Dusty WDs in the $WISE$ All Sky Survey $\cap$ SDSS
• Spitzer 24 um Survey for Dust Disks around Hot White Dwarfs
• Non-LTE models for the gaseous metal component of circumstellar discs around white dwarfs
• High ions towards white dwarfs: circumstellar line shifts and stellar temperature
• SDSS J074511.56+194926.5: Discovery of a Metal-Rich and Tidally Distorted Extremely Low Mass White Dwarf
• A Pilot Search for Evidence of Extrasolar Earth-analog Plate Tectonics
• ALMA and Herschel Observations of the Prototype Dusty and Polluted White Dwarf G29-38
• The Discovery of a Debris Disk Around the DAV White Dwarf PG 1541+651
• PEWDD: A database of white dwarfs enriched by exo-planetary material
• A Multi-Survey Approach to White Dwarf Discovery
• Distant White Dwarfs in the US Naval Observatory Flagstaff Station Parallax Sample
• A Bayesian Approach to Deriving Ages of Individual Field White Dwarfs
• Ohmic heating of asteroids around magnetic stars
• Near-infrared variability in dusty white dwarfs: tracing the accretion of planetary material
• On the role of resonances in polluting white dwarfs by asteroids
• The gaseous debris disk of the white dwarf SDSS J1228+1040. HST/COS search for far-ultraviolet signatures
• A CHEOPS White Dwarf Transit Search
• Evidence of Rocky Planetesimals Orbiting Two Hyades Stars
• The polluted atmosphere of the white dwarf NLTT 25792 and the diversity of circumstellar environments
• A power law decay evolution scenario for polluted single white dwarfs
• The WIRED Survey III: An Infrared Excess around the Eclipsing Post-Common Envelope Binary SDSS J030308.35+005443.7
• Circumstellar Disks at White Dwarfs: Observations
• Non-LTE spectral models for the gaseous debris-disk component of Ton 345
• Can tidal evolution lead to close-in planetary bodies around white dwarfs I: Orbital period distribution
• Can tidal evolution lead to close-in planetary bodies around white dwarfs II: volcanism and transits
• Precise determination of stellar parameters of the ZZ Ceti and DAZ white dwarf GD 133 through asteroseismology
• Finding rocky asteroids around white dwarfs by their periodic thermal emission
• Two substellar survivor candidates; one found and one missing
• Dust Accretion onto Exoplanets
• Gaia white dwarfs with infrared excess I. The 100 pc catalogue
• J-PLUS: The fraction of calcium white dwarfs along the cooling sequence
• Binary asteroid dissociation and accretion around white dwarfs
• I Can Do It With A Broken Planetesimal: Characterising the planetary debris in heavily polluted cool white dwarfs