9922(  1) - 04/04/03 10:18  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9922
                                                       Version: 1
                                                       Check-in Date: 04-Apr-2003
                                                                      10:18:12

1.Proposal Title:
Numerical simulations of outflows in quasars: the microphysics of BAL winds
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Gary Ferland                      University of Kentucky

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5. Abstract

Mass outflow from Broad Absorption Line (BAL) quasars is best studied with resonant
absorption lines that occur across the UV. Analysis of the lines reveals the
chemical composition, energetics, and acceleration of the ejected material, and
offers clues to the physics of the central powerhouse. HST has allowed this
phenomenon to be studied in great detail. HST spectra are analyzed by reference to
large scale plasma simulations which take into account the detailed microphysics of
the gas. However, the presence of such a fast flow changes some of the assumptions
that are the basis of current plasma codes ? in particular the assumption that the
gas is in a local steady state. Actually, the flow introduces advection terms into
all the rate equations, its energetics can affect the thermal balance of the gas,
and high velocities affects the line and continuum transfer. This proposal requests
support for the enhancement of the spectral simulation code Cloudy to make it fully
appropriate for BAL outflows. The specific problems to be addressed are the
radiative transport of lines and continua, which become complicated for such high-
speed flows. I will also create grids of predictions that span the range of
parameters seen in BAL quasars, but which include the effects of the outflow on both
the physical state of the gas and its resulting spectrum.
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                                                9922(  1) - 04/04/03 10:18  - [  2]

            Summary Form for Proposal  9922

  Item                         Used in this proposal
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  Proposal Category            AR
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