First Results from the WIRED Survey John H. Debes (ORAU/GSFC)
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Transcript of First Results from the WIRED Survey John H. Debes (ORAU/GSFC)
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
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 to the sun
– Provide an important catalog for JWST
– Provide lasting research legacy
National Aeronautics and Space AdministrationJet Propulsion LaboratoryCalifornia Institute of Technology
What is WIRED?•WISE IR Excess around Degenerates
(WIRED) Survey
•Merge WISE catalogue with Sloan, 2MASS, and UKIDSS photometry to discover IR-excess sources around white dwarfs
•WIRED has the potential to:
• Detect Dusty White Dwarfs to ~140 pc
• Detect T2 or earlier companions to 70 pc
Sensitivity to Companions
•Companion sensitivity depends on Teff
• Taking Teff=10,000 K, WIRED will be sensitive to T2 dwarfs to ~70pc in WISE 1 and WISE 2 bands
WD
WD+T2
Sensitivity to Dust Disks
• Fiducial Disk: G29-38
• WISE S/N=5 sensitivities: 0.08 mJy (3.35μm), 0.1 mJy (4.6μm), 0.8 mJy (12μm) 6 mJy (22μm)
• Detect IR excess in bands 1 & 2 to ~140 pc
• Detect strong silicate features out to ~55 pc
Selection Criteria•Select all Sloan DR4 WDs, search for
NIR/WISE band excesses
•Fit derived parameters to photometry with cooling models to derive provisional distance (Bergeron et al. 1995)
•Fit significant excesses with companion or disk comparisons
•See poster by D. W. Hoard for statistics of the survey
Previously Reported Dusty White Dwarfs
GD 40
WISE1=0.26+/-0.02 mJyWISE2=0.20+/-0.02 mJyIRAC1=0.23+/-0.01IRAC2=0.19+/-0.01
Conclusions•The tip of the iceberg--many more
interesting sources to be found!
•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)
• In May 2011, preliminary WISE catalogue will be publicly available
• In April 2012 full catalogue will be available
The WIRED Team
Stefanie Wachter, (IPAC, lead)
Don W. Hoard (IPAC)Dave T. Leisawitz (GSFC)
Martin Cohen (UCLA)
WISE Science Team
• 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 AdministrationJet Propulsion LaboratoryCalifornia Institute of Technology