The Origins of a Rich Absorption Line Complex in a Quasar at Redshift
  3.45
  We discuss the nature and origin of a rich complex of narrow absorption lines
in the quasar J102325.31+514251.0 at redshift 3.447. We measure nine C
IV(\lambda1548,1551) absorption line systems with velocities from -1400 to
-6200 km/s, and full widths at half minimum ranging from 16 to 350 km/s. We
also detect other absorption lines in these systems, including H I, C III, N V,
O VI, and Si IV. Lower ionisation lines are not present, indicating a generally
high degree of ionisation in all nine systems. The total hydrogen column
densities range from <=10^{17.2} to 10^{19.1}cm^{-2}. We examine several
diagnostics to estimate more directly the location and origin of each absorber.
Four of the systems can be attributed to a quasar-driven outflow based on line
profiles that are smooth and broad compared to thermal line widths. Several
systems also have other indicators of a quasar outflow origin, including
partial covering. Altogether there is direct evidence for 6 of the 9 systems
forming in a quasar outflow. Consistent with a near-quasar origin, eight of the
systems have metallicity values or lower limits in the range Z >= 1-8 Z_{sun}.
The lowest velocity system, which has an ambiguous location, also has the
lowest metallicity, Z <= 0.3 Z_{sun}, and might form in a non-outflow
environment farther from the quasar. Overall, however, this complex of narrow
absorption lines can be identified with a highly structured, multi-component
outflow from the quasar. The high metallicities are similar to those derived
for other quasars at similar redshifts and luminosities, and are consistent
with evolution scenarios wherein quasars appear after the main episodes of star
formation and metal enrichment in the host galaxies.
