  Emission from metal resonant lines has recently emerged as a potentially
powerful probe of the structure of galactic winds at low and high redshift. In
this work, we present only the second example of spatially resolved
observations of NaI D emission from a galactic wind in a nearby galaxy (and the
first 3D observations at any redshift). F05189-2524, a nearby (z=0.043) ultra
luminous infrared galaxy powered by a quasar, was observed with the integral
field unit on the Gemini Multi-Object Spectrograph (GMOS) at Gemini North. NaI
D absorption in the system traces dusty filaments on the near side of an
extended, AGN-driven galactic wind (with projected velocities up to 2000 km/s).
These filaments (A_V < 4) and N(H) < 10^22 cm^-2) simultaneously obscure the
stellar continuum and NaI D emission lines. The NaI D emission lines serve as a
complementary probe of the wind; they are strongest in regions of low
foreground obscuration and extend up to the limits of the field of view
(galactocentric radii of 4 kpc). An azimuthally symmetric Sersic model
extincted by the same foreground screen as the stellar continuum reproduces the
NaI D emission line surface brightness distribution except in the inner regions
of the wind, where some emission-line filling of absorption lines may occur.
The presence of detectable NaI D emission in F05189-2524 may be due to its high
continuum surface brightness at the rest wavelength of NaI D. These data
uniquely constrain current models of cool gas in galactic winds and serve as a
benchmark for future observations and models.
