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We study the connection between the X-ray and ultraviolet (UV) properties of the broad absorption line (BAL) wind in the highly X-ray variable quasar PG 2112+059 by comparing Chandra -ACIS data with contemporaneous UV HST /STIS spectra in three different epochs. We observe a correlation whereby an increase in the equivalent widths (EWs) of the BALs is accompanied by a redder UV spectrum. The growth in the BAL EWs is also accompanied by a significant dimming in soft X-ray emission (⁠|${\lesssim}2 \, \text{keV}$|⁠), consistent with increased absorption. Variations in the hard X-ray emission (⁠|${\gtrsim}2\, \text{keV}$|⁠) are only accompanied by minor spectral variations of the UV-BALs and do not show significant changes in the EW of BALs. These trends suggest a wind-shield scenario where the outflow inclination with respect to the line of sight is decreasing and/or the wind mass is increasing. These changes elevate the covering fraction and/or column densities of the BALs and are likely accompanied by a nearly contemporaneous increase in the column density of the shield. [ABSTRACT FROM AUTHOR]

Past X-ray observations of the nearby luminous quasar PDS 456 (at z = 0.184) have revealed a wide-angle accretion disk wind with an outflow velocity of ∼−0.25c, as observed through observations of its blueshifted iron K-shell absorption line profile. Here we present three new XMM-Newton observations of PDS 456: one in 2018 September where the quasar was bright and featureless and two in 2019 September, 22 days apart, occurring when the quasar was five times fainter and where strong blueshifted lines from the wind were present. During the second 2019 September observation, three broad (σ = 3000 km s−1) absorption lines were resolved in the high-resolution Reflection Grating Spectrometer spectrum that are identified with blueshifted O viii Lyα, Ne ix Heα, and Ne x Lyα. The outflow velocity of this soft X-ray absorber was found to be v/c = −0.258 ± 0.003, fully consistent with an iron K absorber with v/c = −0.261 ± 0.007. The ionization parameter and column density of the soft X-ray component (log ξ = 3.4, NH = 2 × 1021 cm−2) outflow was lower by about 2 orders of magnitude when compared to the high-ionization wind at iron K (log ξ = 5, NH = 7 × 1023 cm−2). Substantial variability was seen in the soft X-ray absorber between the 2019 observations, declining from NH = 1023 to 1021 cm−2 over 20 days, while the iron K component was remarkably stable. We conclude that the soft X-ray wind may originate from an inhomogeneous wind streamline passing across the line of sight that, due to its lower ionization, is located further from the black hole, on parsec scales, than the innermost disk wind. [ABSTRACT FROM AUTHOR]

We investigate extremely red quasars (ERQs), a remarkable population of heavily reddened quasars at redshift z  ∼ 2−3 that might be caught during a short-lived 'blow-out' phase of quasar/galaxy evolution. We perform a near-IR observational campaign using Keck/NIRSPEC, VLT/X-shooter, and Gemini/GNIRS to measure rest-frame optical spectra of 28 ERQs with median infrared luminosity 〈log L (erg s−1)〉 ∼ 46.2. They exhibit the broadest and most blueshifted [O  iii ] λ4959,5007 emission lines ever reported, with widths (w 90) ranging between 2053 and 7227 km s−1, and maximum outflow speeds (v98) up to 6702 km s−1. ERQs on average have [O  iii ] outflows velocities about three times larger than those of luminosity-matched blue quasar samples. This discrepancy can be explained by a strong correlation between [O  iii ] kinematics and i–W3 colour, and not by radio loudness, or higher Eddington ratios. We estimate for these objects that at least 3–5 per cent of their bolometric luminosity is being converted into the kinetic power of the observed wind. Our results reveal that ERQs have the potential to strongly affect the evolution of host galaxies. [ABSTRACT FROM AUTHOR]

Theoretical models have suggested an evolutionary model for quasars, in which most of luminous quasars are triggered by major mergers. It is also postulated that reddening as well as powerful outflows indicate an early phase of activity, close to the merger event. We test this model on a sample of quasars with powerful low-ionization outflows seen in broad iron absorption lines (FeLoBAL). This sample of objects show strong reddening in the optical and fast (∼0.1c) high-column density outflows. We present HST WFC3/IR F160W imaging of 10 FeLoBAL host galaxies at redshifts |$z$| ∼ 0.9 (⁠|$\lambda _{\mathrm{ rest}}\sim 8500\, \mathrm{\mathring{\rm A} }$|⁠). We compare the host galaxy morphologies and merger signatures of FeLoBALs to luminous blue non-BAL quasars from Villforth et al. (2017) of comparable luminosity, which show no excess of merger features compared to inactive control samples. If FeLoBAL quasars are indeed in a young evolutionary state, close in time to the initial merging event, they should have strong merger features. We find that the host galaxies of FeLoBAL quasars are of comparable luminosity to the host galaxies of optical quasars and show no enhanced merger rates. When looking only at quasars without strong point spread function residuals, an enhancement in disturbed and merger rates is seen. While FeLoBAL hosts show weak enhancements over a control of blue quasars, their host galaxies are not dominated by recent major mergers. [ABSTRACT FROM AUTHOR]

We investigate the N  v absorption signal along the line of sight of background quasars, in order to test the robustness of the use of this ion as the criterion to select intrinsic (i.e. physically related to the quasar host galaxy) narrow absorption lines (NALs). We build composite spectra from a sample of ∼ 1000 C  iv absorbers, covering the redshift range 2.55 < z < 4.73, identified in 100 individual sight lines from the XQ-100 Legacy Survey. We detect a statistically significant N  v absorption signal only within 5000 km s−1 of the systemic redshift, |$z_{\rm em}$|⁠. This absorption trough is ∼ 15 σ when only C  iv systems with N (C  iv) > 1014 cm−2 are included in the composite spectrum. This result confirms that N  v offers an excellent statistical tool to identify intrinsic systems. We exploit stacks of 11 different ions to show that the gas in proximity to a quasar exhibits a considerably different ionization state with respect to gas in the transverse direction and intervening gas at large velocity separations from the continuum source. Indeed, we find a dearth of cool gas, as traced by low-ionization species and in particular by Mg  ii, in the proximity of the quasar. We compare our findings with the predictions given by a range of cloudy ionization models and find that they can be naturally explained by ionization effects of the quasar. [ABSTRACT FROM AUTHOR]

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]

Broad absorption lines (BALs) found in a significant fraction of quasar spectra identify highvelocity outflows that might be present in all quasars and could be a major factor in feedback to galaxy evolution. Understanding the nature of these flows requires further constraints on their physical properties, including their column densities, for which well-studied BALs, such as CIV λλ1548,1551, typically provide only a lower limit because of saturation effects. Low abundance lines, such as P V λλ1118,1128, indicate large column densities, implying that outflows more powerful than measurements of C IV alone would indicate. We search through a sample of 2694 BAL quasars from the Sloan Digital Sky Survey III/Baryon Oscillation Spectroscopic Survey data release 9 quasar catalogue for such absorption, and we identify 81 ‘definite’ and 86 ‘probable’ detections of P V broad absorption, yielding a firm lower limit of 3.0–6.2 per cent for the incidence of such absorption among BAL quasars. The P V-detected quasars tend to have stronger C IV and Si IV absorption, as well as a higher incidence of LoBAL absorption, than the overall BAL quasar population. Many of the P V-detected quasars have C IV troughs that do not reach zero intensity (at velocities where P V is detected), confirming that the outflow gas only partially covers the UV continuum source. P V appears significantly in a composite spectrum of non-P V-detected BAL quasars, indicating that P V absorption (and large column densities) is much more common than indicated by our search results. Our sample of P V detections significantly increases the number of known P V detections, providing opportunities for follow-up studies to better understand BAL outflow energetics. [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]

The physical scenario describing the origin of quasar winds remains largely unsettled due to our failure to account for X-ray weak BAL quasars. We approach this problem by studying the relation between the inner part of the outflow which is likely to be shielding the X-ray emission and the UV winds characterized by broad absorption lines (BALs). In particular, we aim to probe the wind-shield connection in the highly X-ray variable BAL quasar PG 2112+059, which has exhibited periods of X-ray weakness and X-ray normality in the past. A set of two 20 ks Chandra observations and two contemporaneous HST observations, separated by at least eight months, combined with a nearly simultaneous archival Chandra -HST observation from 2002, afford us a unique opportunity to study the connection between the shield (which is thought to be responsible for the X-ray absorption) and the ionization state of the wind (observed as UV BAL features; e.g., Civ and Ovi lines) over various timescales. In this review, which was based on a presentation in the XMM-Newton 2015 Science Workshop, we provide background relevant to our study and briefly analyze a recent Chandra observation of our new set of multiwavelength observations of PG 2112+059. (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Iron low-ionization broad absorption lines (FeLoBALs) trace a rare class of quasar outflows with large column densities and potentially large kinetic energies that might be important for 'feedback' to galaxy evolution. In order to probe the physical properties of these outflows, we conducted a multiple-epoch, absorption line variability study of 12 FeLoBAL quasars spanning a redshift range of 0.7 ≤ z ≤ 1.9 over rest-frame time-scales of ∼10 d to 7.6 yr. We detect absorption line variability with ≥8σ confidence in 3 out of the 12 sources in our sample over time-scales of ∼0.6 to 7.6 yr. Variable wavelength intervals are associated with ground- and excited-state Fe II multiplets, the Mg II λλ2796, 2803 doublet, Mg I λ2852, and excited-state Ni II multiplets. The observed variability along with evidence of saturation in the absorption lines favours transverse motions of gas across the line of sight as the preferred scenario, and allows us to constrain the outflow distance from the supermassive black hole to be ≲69, 7, and 60 pc for our three variable sources. In combination with other studies, these results suggest that the outflowing gas in FeLoBAL quasars resides on a range of scales and includes matter within tens of parsecs of the central source. [ABSTRACT FROM AUTHOR]

We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line of sight intercepts at least some lower ionization gas. We derive a number of observational results for C IV BALs separated according to the presence or absence of accompanying lower ionization transitions, including measurements of composite profile shapes, equivalent width (EW), characteristic velocities, composite variation profiles, and EW variability. We also measure the correlations between EW and fractional-EW variability for C IV, Si IV, and Al III. Our measurements reveal the basic correlated changes between ionization level, kinematics, and column density expected in accretion-disk wind models; e.g., lines of sight including lower ionization material generally show deeper and broader C IV troughs that have smaller minimum velocities and that are less variable. Many C IV BALs with no accompanying Si IV or Al III BALs may have only mild or no saturation. [ABSTRACT FROM AUTHOR]