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Michael R. Meyer Steward Observatory, The University of Arizona
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Michael R. Meyer Steward Observatory, The University of Arizona D. Backman (NASA-Ames, D.P.I.) , S.V.W. Beckwith (STScI), J. Bouwman (MPIA), T. Brooke (Caltech), J.M. Carpenter (Caltech), M. Cohen (UC-Berkeley), U. Gorti (NASA-Ames), T. Henning (MPIA), L. Hillenbrand (Caltech, D.P.I.), D. Hines (SSI), D. Hollenbach (NASA-Ames), J. Lunine (LPL), J.S. Kim (Steward), R. Malhotra (LPL), E. Mamajek (CfA), A. Moro-Martin (Princeton ), P. Morris (SSC), J. Najita (NOAO), D. Padgett (SSC), I. Pascucci (Steward), J. Rodmann (MPIA), W. Schlingman (Steward), M. Silverstone (Steward), D. Soderblom (STScI), J.R. Stauffer (SSC), B. Stobie (Steward), S. Strom (NOAO), D. Watson (Rochester), S. Weidenschilling (PSI), S. Wolf (MPIA), and E. Young (Steward). Placing Our Solar System in Context with the Spitzer Space Telescope
Dust from 0.3-3 AU evolves on timescales comparable to the cessation of accretion (cf. C2D) MIR Silverstone et al. (ApJ, Submitted); See also Mamajek et al. 2004; Weinberger et al. 2004; Metchev et al. 2004. Chrondrules? CAI Formation? 3-10 Myr old IRAC. Terrestrial Planets? 10-30 Myr old IRAC.
... Transition time from thick to thinis < 1 Myr (cf. C2D, next 2 slides) MIR Silverstone et al. (ApJ, in press) Cf. Wolk and Walter, 1996; Kenyon and Hartmann, 1995; Prato and Simon, 1995; Skrutskie et al. 1990. Out of a sample of > 70 stars 3-30 Myr old, 5 optically-thick disks, and no optically-thin disks.
Disk timescales - from C2D * Some wTTs do have disks not previously detected, BUT only the younger ones ( ages < 3 to 6 Myr) [ages are ~ uncertain] * 1/2 the young ones lack disks, even at age 0.8 to 1.5 Myr * Age is NOT the only variable Big RED circle: has disk Padgett et al., in prep; Cieza et al., in prep.
Some disks have inner holes * Some wTTs have inner holes, but small fraction of systems. * May be cleared by planet formation * Infer that disk clearing is fast * Planet formation is “fast or not at all” Cieza et al., in prep.
Examples of warm debris (> 100 K)around Sun-like stars are rare (a few %) MIR Warm debris (perhaps 4-6 AU) around 30 Myr old sun-like star! Hines et al. (ApJ, in press); Mamajek et al. poster, this meeting.
...but more common around stars < 100 Myr. MIR Bouwman et al. (in preparation); cf. Beichman et al. (2005); Song et al. (2005), Chen et al. (2005); Kenyon & Bromley (2004)
Solar-type stars in the Pleiades (age ~ 100 Myr) 5 cases of excess at 24 & 33 mm; 2-3 probably real (not bkg) Stauffer et al. 2005; Stauffer et al. poster, this meeting
GAS Detecting Cool Gas in Disks is HARD! Gorti & Hollenbach (2004); also Najita et al. poster, this mtg GAS DETECTABLE HERE GAS MAS DUST MASS
Gas disk lifetimes appear to be < 10 Myr. GAS => No gas rich disk (> 0.1 Mjup) detected. => 20 stars with ages 3-100 Myr Hollenbach et al. (ApJ, 2005); Najita et al. poster, this mtg
Cool Debris Disks (T < 100 K) are fairlycommon (15-20 %) around Sun-like stars FIR 30+- 10 Myr 45 to ??? AU ~1x10-7 Msun Kim et al. 2005, Hillenbrand et al. poster, this mtg; cf. Bryden et al. 2005 700+- 300 Myr 20 to <100 AU ~6.9x10-8 Msun
... evidence for ? FIR • Dynamically hot outer planetesimal belts • Lack of interior planetesimal belts • Clues to the physical state of the remnant disk (e.g. Najita & Williams 2005) HR 8907 Kim et al. 2005; Hillenbrand et al. poster, this mtg
Statistics of FEPS 33 m Detections N/M/F-IR NB: less common at ages > 300 Myr than 70 mm (~ 50 K) detections See also Bryden et al. (2005)
History of our solar system’s dust disk -- are strong old excesses = extrasolar Late Heavy Bombardments? Backman et al. in prep; cf. Gomes et al. (2005); Strom et al. (2005), Levison et al. (PPV), Kenyon & Bromley (2004).
FEPS Preliminary Results: Debris Disk Lifetimes Radius (AU) < 0.1 0.3-1.0 1-10 30-100 3-10 Lifetime (Myr) 10-30 30-100 100-300 300-1000 1000-3000
FEPS posters at this meeting • 63.18 Silverstone et al. • Young, warm debris disks • 63.48 Mamajek et al. • HD 12039 (from Hines et al. in press) • 63.52 Najita et al. • Limits on circumstellar gas • 63.11 Stauffer et al. • Pleiades stars with 24 & 33 mm excesses • 63.28 Hillenbrand et al. • Old, cold debris disks (from Kim et al. 2005) • 63.31 Backman et al. • To-date FEPS results summary