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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]

Broad absorption lines (BALs) in quasar spectra are prominent signatures of high-velocity outflows, which might be present in all quasars and could be a major contributor to feedback to galaxy evolution. Studying the variability in these BALs allows us to further our understanding of the structure, evolution and basic physical properties of the outflows. This is the third paper in a series on a monitoring programme of 24 luminous BAL quasars at redshifts 1.2 < z < 2.9. We focus here on the time-scales of variability in C iv λ1549 BALs in our full multi-epoch sample, which covers time-scales from 0.02 to 8.7 yr in the quasar rest frame. Our sample contains up to 13 epochs of data per quasar, with an average of seven epochs per quasar. We find that both the incidence and the amplitude of variability are greater across longer time-scales. Part of our monitoring programme specifically targeted half of these BAL quasars at rest-frame time-scales ≤2 months. This revealed variability down to the shortest time-scales we probe (8–10 d). Observed variations in only portions of BAL troughs or in lines that are optically thick suggest that at least some of these changes are caused by clouds (or some type of outflow substructures) moving across our lines of sight. In this crossing cloud scenario, the variability times constrain both the crossing speeds and the absorber locations. Specific results also depend on the emission and absorption geometries. We consider a range of geometries and use Keplerian rotational speeds to derive a general relationship between the variability times, crossing speeds and outflow locations. Typical variability times of the order of ∼1 yr indicate crossing speeds of a few thousand km s−1 and radial distances ∼1 pc from the central black hole. However, the most rapid BAL changes occurring in 8–10 d require crossing speeds of 17 000–84 000 km s−1 and radial distances of only 0.001–0.02 pc. These speeds are similar to or greater than the observed radial outflow speeds, and the inferred locations are within the nominal radius of the broad emission-line region. [ABSTRACT FROM PUBLISHER]

Abstract: The current paradigm for the AGN phenomenon is a central engine that consists of an inflow of material accreting in the form of a disk onto a supermassive black hole. Observations in the UV and optical find high velocity ionized material outflowing from the black hole. We present results from Suzaku and XMM-Newton observations of a sample of intrinsic NAL quasars with high velocity outflows. Our derived values of the intrinsic column densities of the X-ray absorbers are consistent with an outflow scenario in which NAL quasars are viewed at smaller inclination angles than BAL quasars. We find that the distributions of and of the NAL quasars of our sample differ significantly from those of BAL quasars and SDSS radio-quiet quasars. The NAL quasars are not significantly absorbed in the X-ray band and the positive values of suggest absorption in the UV band. The positive values of of the intrinsic NAL quasars can be explained in a geometric scenario where our lines of sight towards the compact X-ray hot coronae of NAL quasars do not traverse the absorbing wind whereas lines of sight towards their UV emitting accretion disks do intercept the outflowing absorbers. [Copyright &y& Elsevier]