1. White Dwarfs, Planets, Disks Marc Kuchner NASA Goddard Space Flight Center Laboratory for Exoplanets and Stellar Astrophysics

2. Laboratory for Exoplanets and Stellar Astrophysics NASA Postdoctoral Program: http://nasa.orau.org/postdoc/ Exoplanet Talks: http://eud.gsfc.nasa.gov/ Marc.Kuchner/exoplanetclub.html

3. Spitzer Space Telescope White Dwarf Bill Reach (IPAC) Ted von Hippel, Don Winget, Mukremin Kilic, Fergal Mullaly (UT Austin) Adam Burrows (U. Arizona)

4. Wavelength (microns) White Dwarf G29-38 Zuckerman & Becklin 1987 1200 K 0.15 R sun ~40 Jupiter masses by age and T

5. H He C Mg Fe x=0.75 log mass (solar masses) Radius (Earth Radii) White Dwarf

6. log mass (solar masses) Radius (Earth Radii) HD209458b G29-38b ? Jupiter

7. DO DZ 75% 10% 5% 10% Helium Surface Hydrogen Surface No Lines from Surface! DQ DX Metal, Carbon, Or Unidentified Carbon and Oxygen Core DA DC DB

8. ~20% of DAs, including G29-38 Hydrogen Surface with Metals DAZ CO core

9. T eff (K) Bergeron et al. 2004 DA Instability Strip Log g

10. 615s Power 23 JUL 1988 B-band 24 JUL 1988 K-band Patterson et al. 1991

12. Pulsation Timing (Kleinman et al. 1998) & speckle photometry (Kuchner et al. 1998) HST/Gemini Photometry (Debes et al. 2005) Debes et al. 2005 Log R (AU) M Jupiter Deuterium Burning Limit

16. e.g. Debes & Sigurdsson 2002, Jura et al. 2003

18. Spitzer Space Telescope White Dwarf

19. Jupiter at 5 microns w/ ISO (Encrenaz et al. 1997)

20. Typical WD ages since formation of progenitor are 1.5 - 3.5  10 9 years. Planet mass (M Jupiter ) 0 5 10 15 0.3 0.2 0.1 0.0 Planet/WD at 4.5 microns 10 9 yr. 3  10 9 yr. Spitzer photometry

22. CIA Bergeron et al. 1994

23. Kilic et al. 2006, ApJ, in press Same Models w/ CIA New Spitzer Photometry Without the mid IR data: 5400 K, 3.5 Gyr old. With the mid IR data: 5200 K, 4.5 Gyr old

24. F J /F V F 8  m /F V DZ All Hydrogen WDs below ~7000 K show an 8 micron deficit!

25. Galactic Disk: 8 +/- 1.5 Gyr

26. Von Hippel et al., in prep A New Dusty WD!

27. Kilic et al. 2005 Becklin et al. 2005 Becklin & Zuckerman 1987 Kilic et al., in prep GD 56 Plus 2 more from IRTF and one from Farihi et al makes 5!

31. Amorphous carbon needed to match 1.6  m spectrum amorphous olivine forsterite Reach et al. 2005 C:O ratio 3:1 1-10R Sun 0.01-1000  m grains dn/da  a -3.5

32. Livio, Pringle & Saffer 1992

33. H He C Mg Fe x=0.75 log mass (solar masses) Radius (Earth Radii) White Dwarf CO Giant

34. C:O ratio in gas 9:1 Roberge et al. in press

35. 11.3 micron C-H out-of-plane bend T Tauri Stars -- Spitzer Geers et al 2005

39. Particle Plieups Youdin & Chiang 2004

40. Lodders & Fegley 1997

41. Wood & Hashimoto 1993 Atomic Fraction SiC Forsterite Cohenite Enstatite Fe Enstatite Chondrites? Gas and Graphite

43. Gaidos 2000 Kuchner & Seager 2005

44. Artist: Lynette Cook

45. Solar Composition Kuchner & Seager 2005

46. Carbon Planet Kuchner & Seager 2005

49. Time of Arrival Residuals (  s) w/o planets with non- interacting planets with real planets Konacki & Wolzsczan 03

50. Cool Hydrogen WDs have mid-IR deficits; the inferred age of the Galactic disk is wrong by ~25%. Roughly 1/4 DAZ WDs are dusty. The dust sometimes has silicates----but it may be C rich (e.g. G29-38). Carbon planets may be common; we can recognize them if they are hot. Key Points New Exoplanet Lab at Goddard: come join us as a postdoc or as a speaker!

52. Wavelength (microns) Flux (mJy) A WD Planet With A Dust Disk Reach, Von Hippel & Kuchner et al. 2005

54. Plus one more from Farihi et al. (private comminucation). That makes 5 dusty DAZs out of 20 DAZs with 8 micron Photometery. DAZd ?

55. New Dusty WDs from IRTF: GD56+GD362 (Kilic et al 2006) GD362 also found by Becklin et al. 2006

57. The Sun Galactic Center Carigi et al. 2005

58. Dead Star: White Dwarf G 29-38 Solar System Dust 6 8 10 12 14 Wavelength (microns) Relative brightness

59. Spitzer Sees Ghost of Solar System’s Future Marc Kuchner Goddard Space Flight Center Bill Reach Spitzer Science Center Ted von Hippel University of Texas, Austin

60. Oppenheimer et al. 2001

62. Bergeron & Leggett 2002 UltraCool WDs (<4000 K)