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Quasar outflows have long been recognized as potential contributors to the co-evolution between supermassive black holes (SMBHs) and their host galaxies. The role of outflows in active galactic nucleus (AGN) feedback processes can be better understood by placing observational constraints on wind locations and kinetic energies. We utilize broad absorption line (BAL) variability to investigate the properties of a sample of 71BAL quasarswith P V broad absorption. The presence of P V BALs indicates that other BALs like C IV are saturated, such that variability in those lines favours clouds crossing the line of sight.We use these constraints with measurements of BALvariability to estimate outflowlocations and energetics. Our data set consists of multiple-epoch spectra from the Sloan Digital Sky Survey and MDM Observatory. We detect significant (4σ) BAL variations from 10 quasars in our sample over rest-frame timescales between ≤0.2-3.8 yr. Our derived distances for the 10 variable outflows are nominally ≲1-10 pc from the SMBH using the transverse-motion scenario, and ≲100-1000 pc from the central source using ionization-change considerations. These distances, in combination with the estimated high outflow column densities (i.e. NH ≳ 1022 cm-2), yield outflow kinetic luminosities between ~0.001 and 1 times the bolometric luminosity of the quasar, indicating that many absorber energies within our sample are viable for AGN feedback. [ABSTRACT FROM AUTHOR]

Quasar outflows have been posited as a mechanism to couple supermassive black holes to evolution in their host galaxies.We use multi-epoch spectra from the Hubble Space Telescope (HST) and ground-based observatories to study the outflows in seven quasars that have CIV outflow lines ranging from a classic broad absorption line (BAL) to weaker/narrower 'mini-BALs' across restwavelengths of at least 850-1650 Å. The CIV outflowlines all variedwithin a time frame of ≤1.9 yr (rest). This includes equal occurrences of strengthening and weakening plus the emergence of a new BAL system at -38 800 km s-1 accompanied by dramatic strengthening in a mini-BAL at -22 800 km s-1. We infer from ∼1:1 doublet ratios in P V and other lines that the BAL system is highly saturated with line-of-sight covering fractions ranging from 0.27 to 0.80 in the highest to lowest column density regions, respectively. Three of the mini-BALs also provide evidence for saturation and partial covering based on ∼1:1 doublet ratios.We speculate that the BALs and mini-BALs form in similar clumpy/filamentary outflows, with mini-BALs identifying smaller or fewer clumps along our lines of sight. If we attribute the line variabilities to clumps crossing our lines of sight at roughly Keplerian speeds, then a typical variability time in our study, ∼1.1 yr, corresponds to a distance ∼2 pc from the central black hole. Combining this with the speed and minimum total column density inferred from the P V BAL, NH ≳ 2.5 × 1022 cm-2, suggests that the BAL outflow kinetic energy is in the range believed to be sufficient for feedback to galaxy evolution. [ABSTRACT FROM AUTHOR]