2015MNRAS.454..675C

Using two orbits of HST/COS archival observations, we measure the location and energetics of a quasar outflow from LBQS J1206+1052. From separate collisional excitation models of observed Niii/Niii* and Siii/Siii* troughs, we measure the electron number density n_\scriptscriptstyle e of the outflow. Both independent determinations are in full agreement and yield n_\scriptscriptstyle e =10^3.0  cm^-3. Combining this value of n_\scriptscriptstyle e with photoionization simulations, we determine that the outflow is located 840 pc from the central source. The outflow has a velocity of 1400 km/s, a mass flux of 9 M_☉/yr and a kinetic luminosity of 10^42.8erg/s. The distance finding is much larger than predicted from radiative acceleration models, but is consistent with recent empirical distance determinations.