10972(  1) - 04/03/06 11:16  - [  1]

                  HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 10972

Version: 1    Check-in Time: 03-Apr-2006 15:16:45

Title
The structure of HD100546's self-shadowed circumstellar disk
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Type             Cycle     Parallel Pointing Tolerance
AR               15        <none>
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Investigators
                                                                                     Contact?
    PI: Dr. Alice Quillen                 University of Rochester
   CoI: Mr. Jason Nordhaus                University of Rochester                       N

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Abstract

HD100546 presents a unique opportunity to constrain the vertical structure of a
10Myr old circumstellar disk. The infrared spectral energy distribution (SED),
peaking in the mid-infrared, implies that almost half of the star light is absorbed
by a puffed up inner disk at about 10 AU that shadows the outer disk. Spiral
structure in the outer disk at 200 AU is most likely caused by the shadow of the
inner disk projected onto a warped outer disk. We propose to simultaneously model
both the infrared SED and the scattered light multi-band images observed with the
ACS coronagraph. This work will provide unique constraints on both inner and outer
disk structure, including on the angular structure of the inner disk and on the
geometry of the outer disk. The vertical disk structure is particularly interesting
as at 10 Myr, HD100546?s disk is likely to contain and be forming planetesimals and
planetary embryos. The disk geometry and azimuthal structure will provide
information on the mass distribution and so on planetesimals and planets residing in
this system.
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