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An Analysis of Broad Emission-Line Profiles from HST Data

Published online by Cambridge University Press:  12 April 2016

Stephanie A. Snedden
Affiliation:
Physics and Astronomy Department, University of Nebraska, Lincoln, NE 68588-0111, USA
C. Martin Gaskell
Affiliation:
Physics and Astronomy Department, University of Nebraska, Lincoln, NE 68588-0111, USA

Abstract

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We have analyzed the HST FOS spectra of all quasars in the Stirpe (1990) high S/N line-profile sample and studied line-profile ratios as a function of radial velocity. Some quasars show no sign at all of NLR Lyα. We confirm that Hα is narrower than Lyα (after allowance for NLR contributions). The Lyα/Hα ratios in the cores of the broad lines are all close to or slightly less than case B and values predicted by single-cloud photoionization models. The Lyα/Hα ratio is surprisingly high in the blue wing. With only one exception, the ratios are equal to or greater than the case B value. Intrinsic reddening must be very small in most cases. We also briefly discuss other ratios.

Type
III. Broad-Line Profiles and Variability
Copyright
Copyright © Astronomical Society of the Pacific 1997

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