AAS 195th Meeting, January 2000
Session 56. Active Galaxies at Several Wavelengths
Oral, Thursday, January 13, 2000, 10:00-11:30am, Centennial III

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[56.06] HST STIS Ultraviolet Spectral Evidence of Outflows in Extreme Narrow-Line Seyfert 1 Galaxies

K. M. Leighly, J. P. Halpern (Columbia University)

ASCA X-ray spectra of three narrow-line Seyfert 1 galaxies (NLS1s) have absorption features that, in one interpretation, are from mildly relativistic outflows with velocities between 0.2 and 0.6 c, depending on the identification of the highly ionized oxygen transitions that are hypothesized to be responsible (Leighly et al. 1997, Ap. J. (Letters), 489, L25). We recently obtained ultraviolet spectra with HST\/ STIS of two of these NLS1s, IRAS 13224--3809 and 1H~0707--495, and these spectra show additional evidence for outflows. We will present a model in which the unusual ultraviolet properties of these objects can be understood in the context of the other extreme properties which characterize NLS1s, namely, narrow Balmer lines, rapid X-ray variability, and luminous soft X-ray emission. We also will discuss the apparent redshift distribution of NLS1s, and methods for extending the study of NLS1s to high redshift so that the evolution of this populous class of AGNs can be related to that of ordinary quasars.

This work is supported by NASA grant NAG5-7971 (LTSA) and STScIGO grant 07360.

If you would like more information about this abstract, please follow the link to http://www.astro.columbia.edu/~leighly/research.html. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.

The author(s) of this abstract have provided an email address for comments about the abstract: leighly@astro.columbia.edu

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