SHARC II Image of Fomalhaut Debris Disk

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SHARC II Image of Fomalhaut Debris Disk

• SHARC II image shows a complete ring.
• CSO and Spitzer images are consistent with a
  uniform, inclined, slightly elliptical dust disk
  of radius 150 AU offset from star by 10 AU.
• An unseen planet of gt1 Earth mass can maintain
  this and the small apocentric density
  enhancement.
• Image deconvolves well with HiRes as implemented
  by JPL/Spitzer group, setting a precedent for
  future studies with CSO and CCAT.

Marsh et al. ApJ, Feb 2005
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CSO Image Confirmed in Optical with HST

• Papers have similar conclusions about structure
  of disk and nature of planet required to maintain
  it.

Kalas, Graham, Clampin Nature, June 2005
Marsh et al. ApJ, Feb. 2005
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SHARC II Resolved Debris Disks
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Tentative Detection of Ring in Vega
contours PdBI (Wilner et al. 2002)

• Dust is known to be centrally cleared based on
  the spectral energy distribution (lack of hot
  dust).
• Ring appears to be detected in SHARC II image
  perhaps elliptical or inclined.
• Future plans include deeper imaging at 350 mm and
  450 mm and modeling of planet sculpting (JPL
  group).

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Spectral Energy Distributions of More Distant,
Unresolved Debris Disks
M0
K1 V
log wavelength (mm)
log wavelength (mm)

• SHARC II detections in red (Chen et al., ApJ,
  2005, accepted).
• T 40 K in both cases 10-3 and 10-4 Moon masses
  of dust
• By following up Spitzer detections, we may
  discover colder submillimeter disks.