10649(  1) - 04/05/05 12:17  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10649
                                                       Version: 1
                                                       Check-in Date: 05-Apr-2005
                                                                      16:17:07

1.Proposal Title:
Probing the Circumstellar Environment and Shock Interaction in SN 1987A and Cas A
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2. Proposal For  3. Cycle  4. Parallel Pointing Tolerance
AR               14        <none>
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5. Investigators
                                                                                     Contact?
    PI: Dr. Vikram Dwarkadas              University of Chicago

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6. Abstract

Hubble Space Telescope (HST) observations of Supernovae (SNe) and Supernova Remnants
have revolutionized our knowledge of these objects. The spectacular HST images of SN
1987A have allowed us a real-time look into the impact of the SN shock wave with the
surrounding bipolar nebula, and the development of 'hotspots' along the equatorial
ring. HST and other multi-wavelength data have fostered the development of models
for the structure of the medium surrounding SN 1987A. HST images of the SN remnant
Cas A have revealed an intricate array of knots and filaments, and confirmed that
the ejecta in SNe can be very clumpy in nature. These observations can only be
understood via detailed, and equally high-resolution, numerical modeling that takes
the evolution of the pre-SN star into account. I propose a two-year study to
investigate the interaction of SN shock waves with the ambient medium formed by the
pre-SN star. This study will differ from others in computing the structure of the
circumstellar medium around the star throughout its evolutionary history. The mass-
loss properties at each timestep in the evolution will be computed from the stellar
properties, which are obtained from the latest stellar evolution models. My multi-
dimensional simulations will provide an important step towards understanding the
complex interaction of the shock-wave with the equatorial ring seen in SN 1987A. I
will study the formation of various instabilities, and their effect on the growth
and evolution of small-scale structures as seen in Cas A. Although my work is
motivated primarily by these two objects, the results will be broadly applicable to
a wide variety of phenomena in which shock wave interaction with the ambient medium
is predominant.
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                                                10649(  1) - 04/05/05 12:17  - [  2]

            Summary Form for Proposal  10649

  Item                         Used in this proposal
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  Proposal Category            AR
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