Bal Phosphorus Abundance and Evidence for Immense Ionic Column Densities in Quasar Outflows: VLT/X-Shooter Observations of Quasar SDSS J1512+1119

We present spectroscopic analysis of the broad absorption line (BAL) outflow in quasar SDSS J1512+1119. In particular, we focus our attention on a kinematic component in which we identify P v and S iv /S iv * absorption troughs. The shape of the unblended phosphorus doublet troughs and the three S iv /S iv * troughs allow us to obtain reliable column density measurements for these two ions. Photoionization modeling using these column densities and those of He i * constrain the abundance of phosphorus to the range of 0.5–4 times the solar value. The total column density, ionization parameter, and metallicity inferred from the P v and S iv column densities lead to large optical depth values for the common transition observed in BAL outflows. We show that the true C iv optical depth is ∼1000 times greater in the core of the absorption profile than the value deduced from its apparent optical depth.