7550(  1) - 12/14/96 01:06  - [  0]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      7550
                                                       Version: 1
                                                       Check-in Date: 13-Dec-1996
                                                                      18:23:10

1.Proposal Title:
The Morphology Of Protostellar Environments
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2. Scientific Category   3. Proposal For  4. Cycle
YOUNG STARS AND CIRCU       AR               7
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5. Investigators
                                                                                     Contact?
    PI: Kenneth Wood                      University of Wisconsin
   CoI: Scott Kenyon                      Harvard-Smithsonian Center for                N
                                          Astrophysics

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6. Abstract

This proposal requests archival WFPC2 images of the circumstellar environments of T
Tauri stars. We shall examine differences in the scattered light images of T Tau, HL
Tau, and HH-30 as probes of different stages of star formation seen from different
viewing angles. The scattered light images of T Tau and HL Tau exhibit the
characteristics of light reaching the observer via scattering off the walls of a
cavity carved by jets in the natal dust cloud. T Tau is viewed along a cavity axis;
HL Tau is viewed at higher inclination and shows evidence of multiple cavities.
Previous modeling efforts of HH-30 assumed that circumstellar material forms a disk-
like structure, suggesting that this object is more evolved than T Tau and HL Tau.
We shall investigate whether this is indeed true, since the ``disk'' parameters
adopted in the previous analysis mimic those of infalling envelopes with cavities.
We shall model scattered light images using 3D Monte Carlo radiation transfer codes
that calculate the emergent flux and polarization images. We shall also compare
emergent spectral energy distributions with published optical through far IR spectra
for each object. Thus the modeling effort will use imaging, polarimetry, and
spectroscopy to derive a consistent picture for the circumstellar environments of
these young stellar objects.
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  Data Distribution

  Media:           ELECTRONIC
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:
  Email:                                                              ,
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                                                7550(  1) - 12/14/96 01:06  - [  1]

            Summary Form for Proposal  7550

  Item                         Used in this proposal
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  Proposal Category            AR
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  Scientific Category          YOUNG STARS AND CIRCU
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