9537(  1) - 12/06/01 12:45  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9537
                                                       Version: 1
                                                       Check-in Date: 06-Dec-2001
                                                                      11:48:04

1.Proposal Title:
A Multiwavelength Study of the Cassiopeia A Supernova Remnant
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Lawrence Rudnick                  University of Minnesota
   CoI: Ms. Tracey DeLaney                University of Minnesota                       N
   CoI: Dr. Una Hwang                     NASA/Goddard Space Flight Center              N
   CoI: Dr. Rob Petre                     NASA/Goddard Space Flight Center              N
   CoI: Dr. Robert Fesen                  Dartmouth College                             N
   CoI: Dr. Jon Morse                     Center for Astrophysics and Space             N
                                          Astronomy/University of Colorado

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5. Abstract

We propose to use the WFPC2 archive data on supernova remnant Cas A along with new
and existing Chandra and VLA data, to construct a coherent physical picture of its
multiple interacting thermal and relativistic plasmas. These multiple plasmas have
distinct kinematics and their relationships are poorly understood. There have been
very few multiwavelength studies of any SNRs to date and none have had the high-
resolution detail now available with HST and Chandra. We will first examine the
behavior of shocks in an inhomogeneous environment with a comparison of clump
structures in the optical, X-ray, and radio images. Our second goal is to study the
amplification and ordering of magnetic fields using the Rayleigh-Taylor fingers now
seen for the first time with the HST data. These will be compared with our radio
polarization and our radio and X-ray proper motion measurements to test this shear
amplification picture. Finally, we will use ionization state, structure,
compositional differences, and dynamical information derived from the the optical
and X-ray data to determine how cosmic ray acceleration, as measured by radio
spectral index, is regulated in SNRs. The HST data now allow us to remedy the
incomplete physical pictures derived from the individual wavebands separately, and
make major steps in understanding the coupling between the multiple plasmas which
control the dynamics and radiative properties of Cas A.
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                                                9537(  1) - 12/06/01 12:45  - [  2]

            Summary Form for Proposal  9537

  Item                         Used in this proposal
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  Proposal Category            AR
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