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arXiv · astro-ph/0610435

Hubble Space Telescope Ultraviolet Spectroscopy of Fourteen Low-Redshift Quasars

Abstract

We present low-resolution ultraviolet spectra of 14 low redshift (z<0.8) quasars observed with HST/STIS as part of a Snap project to understand the relationship between quasar outflows and luminosity. By design, all observations cover the CIV emission line. Nine of the quasars are from the Hamburg-ESO catalog, three are from the Palomar-Green catalog, and one is from the Parkes catalog. The sample contains a few interesting quasars including two broad absorption line (BAL) quasars (HE0143-3535, HE0436-2614), one quasar with a mini-BAL (HE1105-0746), and one quasar with associated narrow absorption (HE0409-5004). These BAL quasars are among the brightest known (though not the most luminous) since they lie at z<0.8. We compare the properties of these BAL quasars to the z<0.5 Palomar-Green and z>1.4 Large Bright Quasar samples. By design, our objects sample luminosities in between these two surveys, and our four absorbed objects are consistent with the v ~ L^0.62 relation derived by Laor & Brandt (2002). Another quasar, HE0441-2826, contains extremely weak emission lines and our spectrum is consistent with a simple power-law continuum. The quasar is radio-loud, but has a steep spectral index and a lobe-dominated morphology, which argues against it being a blazar. The unusual spectrum of this quasar resembles the spectra of the quasars PG1407+265, SDSSJ1136+0242, and PKS1004+13 for which several possible explanations have been entertained.

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BibTeXRIS

Rajib Ganguly, Michael S. Brotherton, Nahum Arav, Sara R. Heap, Lutz Wisotzki, Thomas L. Aldcroft, Danielle Alloin, Ehud Behar, Gabriela Canalizo, D. Michael Crenshaw, Martijn de Kool, Kenneth Chambers, Gerald Cecil, Eleni Chatzichristou, John Everett, Jack Gabel, C. Martin Gaskell, Emmanuel Galliano, Richard F. Green, Patrick B. Hall, Dean C. Hines, Vesa T. Junkkarinen, Jelle S. Kaastra, Mary Elizabeth Kaiser, Demosthenes Kazanas, Arieh Konigl, Kirk T. Korista, Gerard A. Kriss, Ari Laor, Karen M. Leighly, Smita Mathur, Patrick Ogle, Daniel Proga, Bassem Sabra, Ran Sivron, Stephanie Snedden, Randal Telfer, Marianne Vestergaard. 2006-10-13. Hubble Space Telescope Ultraviolet Spectroscopy of Fourteen Low-Redshift Quasars. https://doi.org/10.1086/510129

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