Narrow UV Absorption Line Outflows from Quasars
  Narrow absorption line (NAL) outflows are an important yet poorly understood
part of the quasar outflow phenomenon. We discuss one particular NAL outflow
that has high speeds, time variability, and moderate ionizations like typical
BAL flows, at an estimated location just ~5 pc from the quasar. It also has a
total column density and line widths (internal velocity dispersions) ~100 times
smaller than BALs, with no substantial X-ray absorption. We argue that
radiative shielding (in the form of an X-ray/warm absorber) is not critical for
the outflow acceleration and that the moderate ionizations occur in dense
substructures that have an overall small volume filling factor in the flow. We
also present new estimates of the overall incidence of quasar outflow lines;
e.g., ~43% of bright quasars have a C IV NAL outflow while ~68% have a C IV
outflow line of any variety (NAL, BAL, or mini-BAL).
