Zusammenfassung
We present a census of z(abs) < 2, intrinsic (those showing partial coverage)
and associated z(abs) ~ z(em) quasar absorption-line systems detected in the
Hubble Space Telescope archive of Space Telescope Imaging Spectrograph echelle
spectra. This work complements the Misawa et al. (2007) survey of 2 < z(em) < 4
quasars that selects systems using similar techniques. We confirm the existence
of so-called "strong N V" intrinsic systems (where the equivalent width of H I
Ly alpha is small compared to N V 1238) presented in that work, but find no
convincing cases of "strong C IV" intrinsic systems at low redshift/luminosity.
Moreover, we also report on the existence of "strong O VI" systems. From a
comparison of partial coverage results as a function of ion, we conclude that
systems selected by the N V ion have the highest probability of being
intrinsic. By contrast, the C IV and O VI ions are poor selectors. Of the 30 O
VI systems tested, only two of the systems in the spectrum on 3C 351 show
convincing evidence for partial coverage. However, there is a 3-sigma excess in
the number of absorbers near the quasar redshift (|Delta v| <= 5000 km/s) over
absorbers at large redshift differences. In at least two cases, the associated
O VI systems are known not to arise close to the accretion disk of the quasar.
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