9947(  1) - 04/04/03 10:31  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9947
                                                       Version: 1
                                                       Check-in Date: 04-Apr-2003
                                                                      10:31:25

1.Proposal Title:
AGN Radiation-Driven Outflows: Models vs. Observations
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Daniel Proga                      University of Colorado at Boulder
   CoI: Dr. Timothy Kallman               NASA Goddard Space Flight Center              N
   CoI: Prof. Mitchell Begelman           University of Colorado at Boulder             N
   CoI: Dr. Nahum Arav                    University of Colorado at Boulder             N

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5. Abstract

We propose to study mass outflows from active galactic nuclei (AGN). Observations,
many of them obtained by HST, show powerful outflows in such diverse astrophysical
environments as AGN; many types of interacting binary stars; and young stellar
objects. We will focus our theoretical study on the luminous disks in AGN, which are
strong UV sources. Previous studies, including our own, show that accretion disks in
AGN can produce winds driven by radiation pressure due to spectral lines. However,
despite the dramatic increase of high quality observational data and the progress
made in theoretical modeling, there is still little contact between the models and
observations. We propose to change this situation. It can be done within the HST
theory program because there is no new physics needed but rather a better treatment
of well-understood physical processes -- such as photoionization and radiative
transfer -- within the existing radiation-driven disk wind model. In our study, we
will continue to use the multi-dimensional, time-dependent, magnetohydrodynamical
code ZEUS to compute, from first principles, the structures of winds driven from
accretion disks by radiation pressure and thermal expansion. Important ingredients
in this study will be (1) self-consistent calculations of the ionization structure
of the wind and radiative transfer through the wind and (2) calculation of the 2-
dimensional structure of the wind. Results of the project will provide basic
dynamical and kinematical properties of disk winds. We will use these properties to
compute theoretical wind diagnostics, such as line profiles and continuum spectra,
for direct comparison with HST/STIS and other observations.
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                                                9947(  1) - 04/04/03 10:31  - [  2]

            Summary Form for Proposal  9947

  Item                         Used in this proposal
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  Proposal Category            AR
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