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Rajib Ganguly (Penn State University)
Narrow absorption lines (NALs) which are truly intrinsic to the QSO are now known to exist in a much wider range of QSO parameter space than previously thought. Historical surveys in high redshift QSOs (where ultraviolet transitions are observable from the ground in optical wavelength) found statistical excesses of strong NALs [REW(CIV) > 1.5 Å] within 5000 km/s of the QSO emission redshift (so called ``associated'' absorbers) in optically-faint steep-spectrum radio-loud QSOs (e.g., Foltz et al. 1986, ApJ, 307, 504). Recently, it has been found that an excess of NALs exist at high ``ejection'' velocity in radio-quiet QSOs (RQQs) over radio-loud QSOs (RLQs), and in flat-spectrum RLQs over steep-spectrum RLQs (e.g. Richards 2001, ApJS, 133, 53). At low redshift (z<1), there is clear evidence that strong ``associated'' NALs have evolved away. Their weak kin appear in some fraction of all QSOs, but avoid core-dominated, flat-spectrum RLQs (Ganguly et al. 2001, ApJ, 549, 133). I summarize what we currently know about the relationship between intrinsic NALs and their host QSOs and explore whether these three populations (strong associated, weak associated, high ejection velocity) can be incorporated into the accretion-disk/wind scenario.
I gratefully acknowledge funding from NASA through STScI and LTSA and from the National Science Foundation.
The author(s) of this abstract have provided an email address for comments about the abstract: ganguly@astro.psu.edu