HST/COS Observations of Quasar Outflows in the 500-1050 Å Rest Frame. VI. Wide, Energetic Outflows in SDSS J0755+2306

Abstract

We present the analysis of two outflows (S1 at -5500 km s^-1 and S2 at -9700 km s^-1) seen in recent Hubble Space Telescope/Cosmic Origins Spectrograph observations of quasar SDSS J0755+2306 (z = 0.854). The outflows are detected as absorption troughs from both high-ionization species, including N III, O III, and S IV, and very high-ionization species, including Ar VIII, Ne VIII, and Na IX. The derived photoionization solutions show that each outflow requires a two ionization-phase solution. For S1, troughs from S IV* and S IV allow us to derive an electron number density, n_e = 1.8 × 10⁴ cm^-3, and its distance from the central source of R = 270 pc. For S2, troughs from O III* and O III yield n_e = 1.2 × 10³ cm^-3 and R = 1600 pc. The kinetic luminosity of S2 is >12% of the Eddington luminosity for the quasar and, therefore, can provide strong AGN feedback effects. Comparison of absorption troughs from O III and O VI in both outflow systems supports the idea that for a given element, higher-ionization ions have larger covering fractions than lower-ionization ones.