Metal-Enriched Outflows in the Ultra-Luminous infrared Quasar Q1321+058
  Quasar outflows may play important role in the evolution of its host galaxy
and central black hole. In this paper, we present a detailed study of multiple
outflows in the obscured ultra-luminous infrared quasar Q1321+058. The outflows
reveal themselves in the complex optical and UV emission line spectrum, with a
broad component blueshifted by 1650 km/s and a narrow component by 360 km/s,
respectively.The higher velocity component shows ever strong N III] and strong
Si III], in addition to strong [O III]5007 and [Ne III]3869 emission lines,
suggesting an overabundance of N and Si relative to C. The abundance pattern is
consistent a fast chemical enriching process associated with a recent
starburst. The outflow extends to several tens to hundred parsecs from the
quasar, and covers only a very small sky. We find that the outflow with line
emitting gas is energetically insufficient to remove the ISM of the host
galaxy. The velocity range and the column density suggest that the outflow
might be part of the low ionization broad absorption line region as seen in a
small class of quasars. The optical and UV continuum is starlight-dominated and
can be modelled with a young-aged (1 Myr) plus an intermediate-aged (~0.5-1
Gyr) stellar populations, suggesting a fast building of the stellar mass in the
host galaxy, consistent with the starburst-type metal abundances inferred from
the high velocity outflow spectrum. The broad band spectral energy distribution
shows that it is an obscured quasar with its bulk emission in the middle
infrared. The star formation rate, independently estimated from UV,
far-infrared, and emission line luminosity, is much lower than that is required
for the co-evolution of the black hole and its host spheroid.
