AAS 199th meeting, Washington, DC, January 2002
Session 99. AGN - Narrow Line and Broad Line
Display, Wednesday, January 9, 2002, 9:20am-6:30pm, Exhibit Hall

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[99.07] Unusual BAL Quasars from the SDSS

P.B. Hall (Princeton/Catolica), S.F. Anderson (U. Washington), M.A. Strauss, G.R. Knapp (Princeton), G.T. Richards, D.P. Schneider (Penn State), D.G. York (U. Chicago)

The Sloan Digital Sky Survey has confirmed the existence of populations of broad absorption line quasars (BALs) with various unusual properties. We discuss the implications of the wide range of properties seen in these objects for models of BAL outflows and quasars in general.

We have discovered one object with a record number of absorption lines. Two other objects with similarly complex absorption show broad \ion{Mg}{2} absorption extending redward of their systemic host galaxy redshifts. This can be explained as absorption of an extended continuum source by a rotation-dominated disk wind.

Five other objects have absorption which removes an unprecedented ~95% of the flux blueward of \ion{Mg}{2}. The absorption in one of them has varied significantly across the ultraviolet in only six months (rest frame).

Numerous reddened BALs have been found, including at least one reddened mini-BAL with very strong \ion{Fe}{2} emission. The five reddest objects have continuum reddenings E(B-V)~q0.5, and in two we find strong evidence that the reddening curve is even steeper than that of the SMC.

We have found at least one object with absorption from \ion{Fe}{3} but not \ion{Fe}{2}, which may be due to an unusually hot and dense low-ionization outflow.

Finally, we have found two luminous, probably reddened high-redshift objects which may be BALs whose outflows partially cover different emission regions as a function of velocity.

PBH acknowledges financial support from Chilean grant FONDECYT/1010981 and a Fundación Andes grant, MAS from NSF grant AST-0071091, and DPS and GTR from NSF grant 99-00703.

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