10691(  1) - 04/05/05 12:41  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10691
                                                       Version: 1
                                                       Check-in Date: 05-Apr-2005
                                                                      16:40:47

1.Proposal Title:
Accuracy of Quasar Black Hole Mass Estimates
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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. Marianne Vestergaard          University of Arizona
   CoI: Dr. Matthias Dietrich             The Ohio State University Research            N
                                          Foundation
   CoI: Dr. Ari Laor                      Technion-Israel Institute of Technology       N
   CoI: Prof. Bradley M. Peterson         The Ohio State University Research            N
                                          Foundation

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6. Abstract

We propose to quantify the accuracy to which black hole masses in high-redshift
quasars can be estimated by using single-epoch spectra and scaling relationships
that relate broad-line region size to luminosity. This study will be based on the
large existing databases of UV and optical HST spectra and ground-based optical
spectra from previous monitoring programs on the 36 active galactic nuclei with
reverberation-based black hole mass measurements. Scaling relationships based on
reverberation results can be and are already being used to estimate black hole
masses at high redshift, as they are easy to use and it is the only method of mass
estimation that is at present straightforwardly extendable to large samples of
distant, luminous quasars. Knowledge of the efficacy, accuracy, and limitations of
the methods used to estimate black hole masses at high-z is crucial to our quest to
advance our understanding of structure growth and evolution in the early Universe.
This study will also address the systematic errors that can be encountered when
applying this methodology to narrow-line Seyfert 1 galaxies. We will consider in
detail the slope of the radius-luminosity relationship for the C IV emission line in
light of recent HST evidence that the slope of this relationship differs from that
of the radius-luminosity relationship for the Balmer lines.
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                                                10691(  1) - 04/05/05 12:41  - [  2]

            Summary Form for Proposal  10691

  Item                         Used in this proposal
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  Proposal Category            AR
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