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R. Ganguly, M. Eracleous, J.C. Charlton, C.W. Churchill (Penn State Univ.)
We have searched HIRES/Keck~I spectra of six quasars for
associated systems (<~5000~km~s-1) selected by
{C~{\sc iv}~\lambda\lambda1548,1550} narrow absorption
lines (NALs). We find five such systems toward four of these
quasars. Three systems show evidence for partial coverage
implying an intrinsic origin. Adding them to three other
intrinsic NALs from the literature increases the available
sample of HIRES/Keck spectra of intrinsic NALs to six. We
extend the technique of
Barlow~&~Sargent~(1997,~AJ,~113,~136) to separately
constrain the coverage fractions of the continuum and broad
emission line (BEL) sources. In at least two of the six
intrinsic systems, {PG~1222+228} (this work) and
{Q~2343+125} (Hamann~et~al.~1997,~ApJ,~478,~87), the
{\it~continuum} source is partially covered (Cc<50%).
This implies small cloud sizes (c. The continuum of the other four
systems may also be partially covered. Based on our small
collection, intrinsic NALs are observed in both radio-quiet
and radio-loud objects with no apparent preference for
radio-loud objects, as suggested by
Anderson~et~al.~(1987,~AJ,~94,~278). These factors could be
diagnostic of similar conditions in some region near the
central engines of these quasars observed along some, but
not all, lines of sight. While it is possible that the
latter could arise from a separate population of quasars
without intrinsic NALs, it is equally feasible that the
cloud distribution is such that certain lines of sight have
zero coverage while others exhibit partial coverage.
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