9514(  1) - 12/06/01 12:29  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9514
                                                       Version: 1
                                                       Check-in Date: 06-Dec-2001
                                                                      11:42:55

1.Proposal Title:
Unified Models and Instabilities of Protoplanetary Disks
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Eugene Chiang                     University of California at Berkeley
   CoI: Dr. Karl Stapelfeldt              Jet Propulsion Laboratory                     N
   CoI: Dr. Alycia Weinberger             Carnegie Institution of Washington            N

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5. Abstract

Dusty disks surrounding young stars contain the raw material from which planets
form. Both terrestrial planets and giant planet cores are built of silicates and
ices that begin as circumstellar dust. How much condensable material resides in
these disks and how is it distributed spatially? What is the range in grain sizes?
What is the dust temperature field? We propose a theoretical investigation to answer
these questions using state-of-the-art radiative transfer models. Our input data
includes scattered light images obtained with the Hubble Space Telescope (HST), the
thermal spectral energy distribution (SED), and mid-infrared and millimeter-wave
maps. By combining these data sets under a unified multi-wavelength analysis, we
break degeneracies in fitted disk parameters that arise when using data from a
single bandpass. We propose further to explain the surprisingly rippled surface
geometry of the disk surrounding TW Hydra, as measured with HST by Krist et al.
(2000). Externally irradiated disks may be susceptible to the spontaneous growth of
ripples in their photospheres. We ask whether ripples can amplify to the point where
certain disk annuli are shadowed from central starlight, and whether they can
transport angular momentum. Our investigations find direct application to the T
Tauri systems TW Hya, GM Aur, HH 30, Haro 6-5b, and HK Tau/c, all of which have been
extensively observed by HST.
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                                                9514(  1) - 12/06/01 12:29  - [  2]

            Summary Form for Proposal  9514

  Item                         Used in this proposal
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  Proposal Category            AR
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