Characterizing the UV and X-ray Outflow in Mrk 509
  We observed Mrk 509 during the fall of 2009 during a multiwavelength campaign
using XMM-Newton, Chandra, HST/COS, SWIFT, and Integral. The 600-ks XMM/RGS
spectrum finds two kinematic components and a discrete distribution of ionized
absorbers. Our high S/N COS spectrum detects additional complexity in the known
UV absorption troughs from a variety of sources in Mrk 509, including the
outflow from the active nucleus, the ISM and halo of the host galaxy, and
infalling clouds or stripped gas from a merger that are illuminated by the AGN.
The UV absorption only partially covers the emission from the AGN nucleus with
covering fractions lower than those previously seen with STIS, and are
comparable to those seen with FUSE. Given the larger apertures of COS and FUSE
compared to STIS, we favor scattered light from an extended region near the AGN
as the explanation for the partial covering. As observed in prior X-ray and UV
spectra, the UV absorption has velocities comparable to the X-ray absorption,
but the bulk of the ultraviolet absorption is in a lower ionization state with
lower total column density than the gas responsible for the X-ray absorption.
Variability compared to prior UV spectra lets us set limits on the location,
density, mass flux, and kinetic energy of the outflowing gas. For component 1
at $-400 \rm km s^{-1}$, the kinetic energy flux of both the UV and the X-ray
outflow is insufficient to have a significant impact on further evolution of
the host galaxy.
