Born Again Disks as Signposts for Planets

John H. DebesSpace Telescope Science Institute

Slide from B. Gaensicke

Slide from B. Gaensicke

Slide from B. Gaensicke

Dusty White Dwarfs are Signposts for

Planets• In 1987, the ZZ Ceti G29-38 was discovered to have an infrared excess

• Excess first attributed to brown dwarf, eventually attributed to dust (i.e. Graham et al., 1991) Zuckerman & Becklin

(1987)

Data from Reach et al. (2005)

Rin=10 RWD

Rout=30 RWD

StructureAfter Jura (2003), Jura et al., (2007), Reach et al., (2009)

Dust Sublimation Tidal Disruption Radius

Slide from B. Gaensicke

Gaseous WD Disks Are Signposts

Metal line White Dwarfs are

Signposts for Planets• G29-38 also

showed absorption lines due to Ca, Mg, and Fe

• Large telescopes with high resolution spectrographs discovered that 25% of WDs have metal pollution (Zuckerman et al., 2003; Koester et al., 2005)Debes et al. (2010)

CompositionZuckerman et al. (2007)

COS can find exquisite

abundances

Gaensicke et al. (2011, in prep)

+ =

Planetesimal Survival

Dong et al., (2010)

Survival of Planetesimals

Sublimation

Lmax=2x104 Lʘ

Gas Drag

3 Mʘ

1.5 Mʘ

1 MʘLmax=104 Lʘ

How do you get asteroids in?

Debes & Sigurdsson (2002)

Unstable Planets

Bonsor et al., (2011)

Exterior Resonances

Debes et al., in prep

Interior Resonances

Accretion from Interior

Resonances

Gaensicke COS Survey

Debes et al., in prep

Predict Belt Masses from Polluted WDs

Debes et al., in prep

For more info, check out this

new book!

Wide-field Infrared Survey Explorer

WISE Mission Overview

Salient FeaturesSalient Features• 4 imaging channels covering 3 - 25 microns 4 imaging channels covering 3 - 25 microns

wavelengthwavelength• 40 cm telescope operating at <17K40 cm telescope operating at <17K• Two stage solid hydrogen cryostatTwo stage solid hydrogen cryostat

• Delta launch from WTR on December 14, 2009 Delta launch from WTR on December 14, 2009 • Sun-synchronous 6am/6pm 500km orbitSun-synchronous 6am/6pm 500km orbit• Scan mirror provides efficient mappingScan mirror provides efficient mapping

• Operational life: estimate 11 monthsOperational life: estimate 11 months• 4 TDRSS tracks per day4 TDRSS tracks per day

Salient FeaturesSalient Features• 4 imaging channels covering 3 - 25 microns 4 imaging channels covering 3 - 25 microns

wavelengthwavelength• 40 cm telescope operating at <17K40 cm telescope operating at <17K• Two stage solid hydrogen cryostatTwo stage solid hydrogen cryostat

• Delta launch from WTR on December 14, 2009 Delta launch from WTR on December 14, 2009 • Sun-synchronous 6am/6pm 500km orbitSun-synchronous 6am/6pm 500km orbit• Scan mirror provides efficient mappingScan mirror provides efficient mapping

• Operational life: estimate 11 monthsOperational life: estimate 11 months• 4 TDRSS tracks per day4 TDRSS tracks per day

ScienceScience• Sensitive all sky survey with 8X redundancySensitive all sky survey with 8X redundancy

– Find the most luminous galaxies in the universe– Find the closest stars+brown dwarfs to the sun– Provide an important catalog for JWST– Provide lasting research legacy

ScienceScience• Sensitive all sky survey with 8X redundancySensitive all sky survey with 8X redundancy

– Find the most luminous galaxies in the universe– Find the closest stars+brown dwarfs to the sun– Provide an important catalog for JWST– Provide lasting research legacy

National Aeronautics and Space Administration

Jet Propulsion LaboratoryCalifornia Institute of Technology

• Dominic Benford - GSFC• Andrew Blain - Caltech• Martin Cohen - UCB• Roc Cutri - IPAC• Peter Eisenhardt -JPL• Nick Gautier - JPL• Tom Jarrett - IPAC• Davy Kirkpatrick - IPAC• David Leisawitz - GSFC• Carol Lonsdale - NRAO

• Amy Mainzer - JPL• John Mather - GSFC• Ian McLean - UCLA• Robert McMillan - UA• Bryan Mendez - UCB• Deborah Padgett - IPAC• Michael Ressler - JPL• Michael Skrutskie - UVa• Adam Stanford - LLNL• Russell Walker - MIRA

PI: Edward L. Wright - UCLA

National Aeronautics and Space Administration

Jet Propulsion LaboratoryCalifornia Institute of Technology

The WIRED Team

Stefanie Wachter, (IPAC, lead)

Don W. Hoard (IPAC)Dave T. Leisawitz (GSFC)

Martin Cohen (MIRA)

WISE Nominal

Sensitivities

Debes et al., ApJS, submitted

Debes et al., ApJS, submitted

Known Disk

Circumbinary Dust

Known WDs

The Take Home Messages

•Dusty/Polluted/Gaseous Disk WDs need at least ONE giant planet to exist

•Mass and location of such planets may be constrained (and observed in the future with HST/JWST)

• IR+photospheric absorption lines give you detailed composition of exoasteroids

Take Home Messages-2•WIRED will provide a host of new

candidates that need to be confirmed and characterized

•WIRED will provide variability info for known dusty white dwarfs

•WISE will provide legacy information as known WDs become complete to ~100pc (currently, only complete to ~20pc)

•Preliminary WISE catalogue is publicly available