  High velocity (HV) outflows are an important but poorly understood aspect of
quasar/SMBH evolution. Outflows during the luminous accretion phase might play
a critical role in "unveiling" young dusty AGN and regulating star formation in
the host galaxies. Most quasar studies have focussed on the broad absorption
lines (BALs). We are involved in a program to study a nearly unexplored realm
of quasar outflow parameter space: HV winds with v>10,000 km/s up to v~0.2c but
small velocity dispersions (narrow absorption lines), such that (Delta v)/v <<
1. Narrow-line HV flows merit specific attention because they complement the
BAL work and pose unique challenges for models of the wind acceleration, mass
loss rates, launch radii, geometry, etc. We have selected the brightest quasars
at 1.8<z<3.5 with candidate narrow HV outflow lines (CIV 1548 A) in existing
SDSS spectra and followed up with monitoring observations to i) characterize,
for the first time, the variability in a sample of absorbers spanning a wide
range of velocities and FWHMs, including some marginal BALs, ii)
identify/confirm more of the true outflow systems, e.g., among the more
ambiguous narrow lines, and iii) test the wind models and derive better
constraints on basic outflow properties, such as the kinematics, locations, and
physical conditions.
