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The local (z=0.0315) AGN Mrk 817, was monitored over more than 500 days with space-borne and ground-based instruments as part of a large international campaign AGN STORM 2. Here, we present a comprehensive analysis of the broad-band continuum variations using detailed modeling of the broad line region (BLR), several types of disk winds classified by their optical depth, and new numerical simulations. We find that diffuse continuum (DC) emission, with additional contributions from strong and broad emission lines, can explain the continuum lags observed in this source during high and low luminosity phases. Disk illumination by the variable X-ray corona contributes only a small fraction of the observed continuum lags. Our BLR models assume radiation pressure-confined clouds distributed over a distance of 2-122 light days. We present calculated mean-emissivity radii of many emission lines, and DC emission, and suggest a simple, transfer-function-dependent method that ties them to cross-correlation lag determinations. We do not find clear indications for large optical depth winds but identify the signature of lower column density winds. In particular, we associate the shortest observed continuum lags with a combination of tau(1 Ryd) approx. 2 wind and a partly shielded BLR. Even smaller optical depth winds may be associated with X-ray absorption features and with noticeable variations in the width and lags of several high ionization lines like HeII and CIV. Finally, we demonstrate the effect of torus dust emission on the observed lags in the i and z bands., Comment: 23 pages, 18 figures. Corrected typographical error in the title of the paper as it appeared in the Metadata

X-ray reverberation mapping is a powerful technique for probing the innermost accretion disk, whereas continuum reverberation mapping in the UV, optical, and infrared (UVOIR) reveals reprocessing by the rest of the accretion disk and broad-line region (BLR). We present the time lags of Mrk 817 as a function of temporal frequency measured from 14 months of high-cadence monitoring from Swift and ground-based telescopes, in addition to an XMM-Newton observation, as part of the AGN STORM 2 campaign. The XMM-Newton lags reveal the first detection of a soft lag in this source, consistent with reverberation from the innermost accretion flow. These results mark the first simultaneous measurement of X-ray reverberation and UVOIR disk reprocessing lags$\unicode{x2013}$effectively allowing us to map the entire accretion disk surrounding the black hole. Similar to previous continuum reverberation mapping campaigns, the UVOIR time lags arising at low temporal frequencies are longer than those expected from standard disk reprocessing by a factor of 2-3. The lags agree with the anticipated disk reverberation lags when isolating short-timescale variability, namely timescales shorter than the H$\beta$ lag. Modeling the lags requires additional reprocessing constrained at a radius consistent with the BLR size scale inferred from contemporaneous H$\beta$-lag measurements. When we divide the campaign light curves, the UVOIR lags show substantial variations, with longer lags measured when obscuration from an ionized outflow is greatest. We suggest that, when the obscurer is strongest, reprocessing by the BLR elongates the lags most significantly. As the wind weakens, the lags are dominated by shorter accretion disk lags., Comment: 28 pages, 11 figures, 3 tables. Accepted for publication in the Astrophysical Journal

We observed the Seyfert 1 galaxy Mrk817 during an intensive multi-wavelength reverberation mapping campaign for 16 months. Here, we examine the behavior of narrow UV absorption lines seen in HST/COS spectra, both during the campaign and in other epochs extending over 14 years. We conclude that while the narrow absorption outflow system (at -3750 km/s with FWHM=177 km/s) responds to the variations of the UV continuum as modified by the X-ray obscurer, its total column density (logNH =19.5 cm-2) did not change across all epochs. The adjusted ionization parameter (scaled with respect to the variations in the Hydrogen ionizing continuum flux) is log UH =-1.0. The outflow is located at a distance smaller than 38 parsecs from the central source, which implies a hydrogen density of nH > 3000 cm-3. The absorption outflow system only covers the continuum emission source and not the broad emission line region, which suggests that its transverse size is small (< 1e16 cm), with potential cloud geometries ranging from spherical to elongated along the line of sight., Comment: 18 pages, 12 Figures, Accepted for publication in ApJ

We present the results of the XMM-Newton and NuSTAR observations taken as part of the ongoing, intensive multi-wavelength monitoring program of the Seyfert 1 galaxy Mrk 817 by the AGN Space Telescope and Optical Reverberation Mapping 2 (AGN STORM 2) Project. The campaign revealed an unexpected and transient obscuring outflow, never before seen in this source. Of our four XMM-Newton/NuSTAR epochs, one fortuitously taken during a bright X-ray state has strong narrow absorption lines in the high-resolution grating spectra. From these absorption features, we determine that the obscurer is in fact a multi-phase ionized wind with an outflow velocity of $\sim$5200 km s$^{-1}$, and for the first time find evidence for a lower ionization component with the same velocity observed in absorption features in the contemporaneous HST spectra. This indicates that the UV absorption troughs may be due to dense clumps embedded in diffuse, higher ionization gas responsible for the X-ray absorption lines of the same velocity. We observe variability in the shape of the absorption lines on timescales of hours, placing the variable component at roughly 1000 $R_g$ if attributed to transverse motion along the line of sight. This estimate aligns with independent UV measurements of the distance to the obscurer suggesting an accretion disk wind at the inner broad line region. We estimate that it takes roughly 200 days for the outflow to travel from the disk to our line of sight, consistent with the timescale of the outflow's column density variations throughout the campaign.

Multi-wavelength spectroscopy of NGC 5548 revealed remarkable changes due to presence of an obscuring wind from the accretion disk. This broadened our understanding of obscuration and outflows in AGN. Swift monitoring of NGC 5548 shows that over the last 10 years the obscuration has gradually declined. This provides a valuable opportunity for analyses that have not been feasible before because of too much obscuration. The lowered obscuration, together with the high energy spectral coverage of Chandra HETG, facilitate the first study of X-ray absorption lines in the obscured state. The comparison of the lines (Mg XI, Mg XII, Si XIII, and Si XIV) between the new and historical spectra reveals interesting changes, most notably the He-like absorption being significantly diminished in 2022. Our study finds that the changes are caused by an increase in both the ionization parameter and the column density of the warm-absorber outflow in the obscured state. This is contrary to the shielding scenario that is evident in the appearance of the UV lines, where the inner obscuring wind shields outflows that are located further out, thus lowering their ionization. The X-ray absorption lines in the HETG spectra appear to be unaffected by the obscuration. The results suggest that the shielding is complex since various components of the ionized outflow are impacted differently. We explore various possibilities for the variability behavior of the X-ray absorption lines and find that the orbital motion of a clumpy ionized outflow traversing our line of sight is the most likely explanation., Comment: Accepted for publication in The Astrophysical Journal (ApJ), 9 pages, 5 figures

We have identified a broad absorption line (BAL) outflow in the HST/STIS spectrum of the quasar QSO B0254-3327B at velocity $v=-3200\text{ km s$^{-1}$}$. The outflow has absorption troughs from ions such as Ne VIII, Na IX, Si XII, and Ne V. We also report the first detection of S XIV absorption troughs, implying very high ionization. Via measurement of the ionic column densities, photoionization analysis, and determination of the electron number density of the outflow, we found the kinetic luminosity of the outflow system to be up to $\sim1\%$ of the quasar's Eddington luminosity, or $\sim5\%$ of the bolometric luminosity, making it a potential contributor to AGN feedback. A solution with two ionization phases was needed, as a single phase was not sufficient to satisfy the constraints from the measured ionic column densities. We find that the ionization parameter of the very high-ionization phase of the outflow is within the expected range of an X-ray warm absorber. We also examined the physical properties of the outflow of Q0254-334 along with previously studied extreme UV outflows, with a total sample of 24 outflow systems, finding a weak negative correlation between outflow velocity and distance from the central source, with larger distances corresponding to slower velocities. The very high-ionization phase of the Q0254-334 outflow has one of the highest ionization parameters of UV absorption outflows to date, which we attribute to the presence of S XIV., Comment: 13 pages, 14 figures. Accepted for publication by MNRAS

We fit the UV/optical lightcurves of the Seyfert 1 galaxy Mrk 817 to produce maps of the accretion disk temperature fluctuations $\delta T$ resolved in time and radius. The $\delta T$ maps are dominated by coherent radial structures that move slowly ($v \ll c$) inwards and outwards, which conflicts with the idea that disk variability is driven only by reverberation. Instead, these slow-moving temperature fluctuations are likely due to variability intrinsic to the disk. We test how modifying the input lightcurves by smoothing and subtracting them changes the resulting $\delta T$ maps and find that most of the temperature fluctuations exist over relatively long timescales ($\sim$100s of days). We show how detrending AGN lightcurves can be used to separate the flux variations driven by the slow-moving temperature fluctuations from those driven by reverberation. We also simulate contamination of the continuum emission from the disk by continuum emission from the broad line region (BLR), which is expected to have spectral features localized in wavelength, such as the Balmer break contaminating the $U$ band. We find that a disk with a smooth temperature profile cannot produce a signal localized in wavelength and that any BLR contamination should appear as residuals in our model lightcurves. Given the observed residuals, we estimate that only $\sim$20% of the variable flux in the $U$ and $u$ lightcurves can be due to BLR contamination. Finally, we discus how these maps not only describe the data, but can make predictions about other aspects of AGN variability., Comment: 23 pages, 18 figures, submitting to ApJ, comments welcome

An intensive reverberation mapping campaign on the Seyfert 1 galaxy Mrk817 using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) revealed significant variations in the response of the broad UV emission lines to fluctuations in the continuum emission. The response of the prominent UV emission lines changes over a $\sim$60-day duration, resulting in distinctly different time lags in the various segments of the light curve over the 14 months observing campaign. One-dimensional echo-mapping models fit these variations if a slowly varying background is included for each emission line. These variations are more evident in the CIV light curve, which is the line least affected by intrinsic absorption in Mrk817 and least blended with neighboring emission lines. We identify five temporal windows with distinct emission line response, and measure their corresponding time delays, which range from 2 to 13 days. These temporal windows are plausibly linked to changes in the UV and X-ray obscuration occurring during these same intervals. The shortest time lags occur during periods with diminishing obscuration, whereas the longest lags occur during periods with rising obscuration. We propose that the obscuring outflow shields the ultraviolet broad lines from the ionizing continuum. The resulting change in the spectral energy distribution of the ionizing continuum, as seen by clouds at a range of distances from the nucleus, is responsible for the changes in the line response., Comment: 20 pages, 8 figures, Accepted for publication in ApJ

The AGN STORM 2 campaign is a large, multiwavelength reverberation mapping project designed to trace out the structure of Mrk 817 from the inner accretion disk to the broad emission line region and out to the dusty torus. As part of this campaign, Swift performed daily monitoring of Mrk 817 for approximately 15 months, obtaining observations in X-rays and six UV/optical filters. The X-ray monitoring shows that Mrk 817 was in a significantly fainter state than in previous observations, with only a brief flare where it reached prior flux levels. The X-ray spectrum is heavily obscured. The UV/optical light curves show significant variability throughout the campaign and are well correlated with one another, but uncorrelated with the X-rays. Combining the Swift UV/optical light curves with Hubble UV continuum light curves, we measure interband continuum lags, $\tau(\lambda)$, that increase with increasing wavelength roughly following $\tau(\lambda) \propto \lambda^{4/3}$, the dependence expected for a geometrically thin, optically thick, centrally illuminated disk. Modeling of the light curves reveals a period at the beginning of the campaign where the response of the continuum is suppressed compared to later in the light curve - the light curves are not simple shifted and scaled versions of each other. The interval of suppressed response corresponds to a period of high UV line and X-ray absorption, and reduced emission line variability amplitudes. We suggest that this indicates a significant contribution to the continuum from the broad line region gas that sees an absorbed ionizing continuum., Comment: 20 pages, 13 figures, 3 tables, accepted for publication in ApJ

We report on a remarkable change in the spectral energy distribution (SED) of Mrk 841, providing new insights on how the soft X-ray excess emission in active galactic nuclei (AGNs) is produced. By Swift monitoring of a sample of Seyfert-1 galaxies, we found an X-ray spectral hardening event in Mrk 841. We thereby triggered our XMM-Newton, NuSTAR, and HST observations in 2022 to study this event. Our previous investigations of such events in other AGNs had shown that they are caused by obscuring winds. However, the event in Mrk 841 has different spectral characteristics and origin. We find it is the soft X-ray excess component that has become dimmer. This is, importantly, accompanied by a similar decline in the optical/UV continuum, suggesting a connection to the soft X-ray excess. In contrast, there is relatively little change in the X-ray power-law and the reflection components. Our SED modeling suggests that the soft X-ray excess is the high-energy extension of the optical/UV disk emission, produced by warm Comptonization. We find the temperature of the disk dropped in 2022, explaining the observed SED dimming. We then examined the Swift data, taken over 15 years, to further decipher the UV and X-ray variabilities of Mrk 841. A significant relation between the variabilities of the X-ray spectral hardness and that of the UV continuum is found, again suggesting that the soft excess and the disk emission are interlinked. This is readily explicable if the soft excess is produced by warm Comptonization., Comment: Published in The Astrophysical Journal Letters (ApJL), 6 pages, 4 figures

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit., Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figures

We present the detection of dust depletion in Complex C, a massive, infalling, low-metallicity high-velocity cloud in the northern Galactic hemisphere that traces the ongoing accretion of gas onto the Milky Way. We analyze a very high signal-to-noise HST/COS spectrum of AGN Mrk 817 formed by coadding 165 individual exposures taken under the AGN STORM 2 program, allowing us to determine dust-depletion patterns in Complex C at unprecedented precision. By fitting Voigt components to the O I, S II, N I, Si II, Fe II, and Al II absorption and applying ionization corrections from customized Cloudy photoionization models, we find sub-solar elemental abundance ratios of [Fe/S]=-0.42+/-0.08, [Si/S]=-0.29+/-0.05, and [Al/S]=-0.53+/-0.08. These ratios indicate the depletion of Fe, Si, and Al into dust grains, since S is mostly undepleted. The detection of dust provides an important constraint on the origin of Complex C, as dust grains indicate the gas has been processed through galaxies, rather than being purely extragalactic. We also derive a low metallicity of Complex C of [S/H]=-0.51+/-0.16 (31% solar), confirming earlier results from this sightline. We discuss origin models that could explain the presence of dust in Complex C, including Galactic fountain models, tidal stripping from the Magellanic Clouds or other satellite galaxies, and precipitation of coronal gas onto dust-bearing ``seed" clouds., Comment: 8 pages, 3 figures, accepted for publication in ApJ Letters. This version has been updated with proof corrections

The AGN STORM 2 collaboration targeted the Seyfert 1 galaxy Mrk 817 for a year-long multiwavelength, coordinated reverberation mapping campaign including HST, Swift, XMM-Newton, NICER, and ground-based observatories. Early observations with NICER and XMM revealed an X-ray state ten times fainter than historical observations, consistent with the presence of a new dust-free, ionized obscurer. The following analysis of NICER spectra attributes variability in the observed X-ray flux to changes in both the column density of the obscurer by at least one order of magnitude ($N_\mathrm{H}$ ranges from $2.85\substack{+0.48\\ -0.33} \times 10^{22}\text{ cm}^{-2}$ to $25.6\substack{+3.0\\ -3.5} \times 10^{22} \text{ cm}^{-2}$) and the intrinsic continuum brightness (the unobscured flux ranges from $10^{-11.8}$ to $10^{-10.5}$ erg s$^{-1}$ cm$^{-2}$ ). While the X-ray flux generally remains in a faint state, there is one large flare during which Mrk 817 returns to its historical mean flux. The obscuring gas is still present at lower column density during the flare but it also becomes highly ionized, increasing its transparency. Correlation between the column density of the X-ray obscurer and the strength of UV broad absorption lines suggests that the X-ray and UV continua are both affected by the same obscuration, consistent with a clumpy disk wind launched from the inner broad line region., Comment: 19 pages, 9 figures, Accepted to ApJ

We present reverberation mapping measurements for the prominent ultraviolet broad emission lines of the active galactic nucleus Mrk817 using 165 spectra obtained with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Our ultraviolet observations are accompanied by X-ray, optical, and near-infrared observations as part of the AGN Space Telescope and Optical Reverberation Mapping Program 2 (AGN STORM 2). Using the cross-correlation lag analysis method, we find significant correlated variations in the continuum and emission-line light curves. We measure rest-frame delayed responses between the far-ultraviolet continuum at 1180 A and Ly$\alpha$ $\lambda1215$ A ($10.4_{-1.4}^{+1.6}$ days), N V $\lambda1240$ A ($15.5_{-4.8}^{+1.0}$days), SiIV + OIV] $\lambda1397$ A ($8.2_{-1.4}^{+1.4}$ days), CIV $\lambda1549$ A ($11.8_{-2.8}^{+3.0}$ days), and HeII $\lambda1640$ A ($9.0_{-1.9}^{+4.5}$ days) using segments of the emission-line profile that are unaffected by absorption and blending, which results in sampling different velocity ranges for each line. However, we find that the emission-line responses to continuum variations are more complex than a simple smoothed, shifted, and scaled version of the continuum light curve. We also measure velocity-resolved lags for the Ly$\alpha$, and CIV emission lines. The lag profile in the blue wing of Ly$\alpha$ is consistent with virial motion, with longer lags dominating at lower velocities, and shorter lags at higher velocities. The CIV lag profile shows the signature of a thick rotating disk, with the shortest lags in the wings, local peaks at $\pm$ 1500 $\rm km\,s^{-1}$, and a local minimum at line center. The other emission lines are dominated by broad absorption lines and blending with adjacent emission lines. These require detailed models, and will be presented in future work., Comment: Submitted to ApJ. 25 pages, 8 figures, and 6 tables

We present the first results from a 100-day Swift, NICER and ground-based X-ray/UV/optical reverberation mapping campaign of the Narrow-Line Seyfert 1 Mrk 335, when it was in an unprecedented low X-ray flux state. Despite dramatic suppression of the X-ray variability, we still observe UV/optical lags as expected from disk reverberation. Moreover, the UV/optical lags are consistent with archival observations when the X-ray luminosity was >10 times higher. Interestingly, both low- and high-flux states reveal UV/optical lags that are 6-11 times longer than expected from a thin disk. These long lags are often interpreted as due to contamination from the broad line region, however the u band excess lag (containing the Balmer jump from the diffuse continuum) is less prevalent than in other AGN. The Swift campaign showed a low X-ray-to-optical correlation (similar to previous campaigns), but NICER and ground-based monitoring continued for another two weeks, during which the optical rose to the highest level of the campaign, followed ~10 days later by a sharp rise in X-rays. While the low X-ray countrate and relatively large systematic uncertainties in the NICER background make this measurement challenging, if the optical does lead X-rays in this flare, this indicates a departure from the zeroth-order reprocessing picture. If the optical flare is due to an increase in mass accretion rate, this occurs on much shorter than the viscous timescale. Alternatively, the optical could be responding to an intrinsic rise in X-rays that is initially hidden from our line-of-sight., Comment: Accepted for publication in the Astrophysical Journal. 15 pages, 8 figures, 3 tables

A decade ago the archetypal Seyfert-1 galaxy NGC 5548 was discovered to have undergone major spectral changes. The soft X-ray flux had dropped by a factor of 30 while new broad and blueshifted UV absorption lines appeared. This was explained by the emergence of a new obscuring wind from the accretion disk. Here we report on the striking long-term variability of the obscuring disk wind in NGC 5548 including new observations taken in 2021-2022 with the Swift Observatory and the Hubble Space Telescope's (HST) Cosmic Origins Spectrograph (COS). The X-ray spectral hardening as a result of obscuration has declined over the years, reaching its lowest in 2022 at which point we find the broad C IV UV absorption line to be nearly vanished. The associated narrow low-ionization UV absorption lines, produced previously when shielded from the X-rays, are also remarkably diminished in 2022. We find a highly significant correlation between the variabilities of the X-ray hardening and the equivalent width of the broad C IV absorption line, demonstrating that X-ray obscuration is inherently linked to disk winds. We derive for the first time a relation between the X-ray and UV covering fractions of the obscuring wind using its long-term evolution. The diminished X-ray obscuration and UV absorption are likely caused by an increasingly intermittent supply of outflowing streams from the accretion disk. This results in growing gaps and interstices in the clumpy disk wind, thereby reducing its covering fractions., Comment: Accepted for publication in The Astrophysical Journal Letters (ApJL), 6 pages, 4 figures

The nearby type-II AGN 1ES1927+654 went through a violent changing-look (CL) event beginning December 2017 during which the optical and UV fluxes increased by four magnitudes over a few months, and broad emission lines newly appeared in the optical/UV. By July 2018 the X-ray coronal emission had completely vanished, only to reappear a few months later. In this work we report the evolution of the radio, optical, UV and X-rays from the pre-flare state through mid-2021 with new and archival data from the Very Long Baseline Array (VLBA), the European VLBI Network, the Very Large Array (VLA), the Telescopio Nazionale Galileo (TNG), Gran Telescopio Canarias (GTC), The Neil Gehrels Swift observatory and XMM-Newton. The main results from our work are: (1) The source has returned to its pre-CL state in optical, UV, and X-ray; the disk-corona relation has been re-established as has been in the pre-CL state, with an $\alpha_{\rm OX}\sim 1.02$. The optical spectra are dominated by narrow emission lines. (2) The UV light curve follows a shallower slope of $\propto t^{-0.91\pm 0.04}$ compared to that predicted by a tidal disruption event. We conjecture that a magnetic flux inversion event is the possible cause for this enigmatic event. (3) The compact radio emission which we tracked in the pre-CL (2014), during CL (2018) and post-CL(2021) at spatial scales $<1$ pc was at its lowest level during the changing look event in 2018, nearly contemporaneous with a low $2-10$ keV emission. The radio to X-ray ratio of the compact source $L_{\rm Radio}/L_{\rm X-ray}\sim 10^{-5.5}$, follows the Gudel-Benz relation, typically found in coronally active stars, and several AGN. (4) We do not detect any presence of nascent jets at the spatial scales of $\sim 5-10$ pc., Comment: Resubmitted to ApJ following minor comments from the referee

We report on the discovery of a UV absorption counterpart of a low-ionization X-ray ultra-fast outflow (UFO) in the Narrow-Line Seyfert-1 galaxy IRAS 17020+4544. This UV signature of the UFO is seen as a narrow and blueshifted Lyman-alpha absorption feature in the far-UV spectrum, taken with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST). The Lyman-alpha feature is found to be outflowing with a velocity of -23430 km/s (0.078 c). We carry out high-resolution UV spectroscopy and photoionization modeling to study the UFO that is seen in the HTS/COS spectrum. The results of our modeling show that the UV UFO corresponds to a low-ionization, low-velocity component of the X-ray UFO found previously with XMM-Newton's Reflection Grating Spectrometer (RGS). The other higher-velocity and higher-ionization components of the X-ray UFOs are not significantly detected in the HST/COS spectrum, consistent with predictions of our photoionization calculations. The multiple ionization and velocity components of the UFOs in IRAS 17020+4544 suggest a scenario where a powerful primary UFO entrains and shocks the ambient medium, resulting in formation of weaker secondary UFO components, such as the one found in the UV band., Comment: Accepted for publication in The Astrophysical Journal (ApJ), 13 pages, 5 figures

The Seyfert-1 galaxy NGC 3516 has undergone major spectral changes in recent years. In 2017 we obtained Chandra, NuSTAR, and Swift observations during its new low-flux state. Using these observations we model the spectral energy distribution (SED) and the intrinsic X-ray absorption, and compare the results with those from historical observations taken in 2006. We thereby investigate the effects of the changing-look phenomenon on the accretion-powered radiation and the ionized outflows. Compared to its normal high-flux state in 2006, the intrinsic bolometric luminosity of NGC 3516 was lower by a factor of 4 to 8 during 2017. Our SED modeling shows a significant decline in the luminosity of all the continuum components from the accretion disk and the X-ray source. As a consequence, the reprocessed X-ray emission lines have also become fainter. The Swift monitoring of NGC 3516 shows remarkable X-ray spectral variability on short (weeks) and long (years) timescales. We investigate whether this variability is driven by obscuration or the intrinsic continuum. We find that the new low-flux spectrum of NGC 3516, and its variability, do not require any new or variable obscuration, and instead can be explained by changes in the ionizing SED that result in lowering of the ionization of the warm-absorber outflows. This in turn induces enhanced X-ray absorption by the warm-absorber outflows, mimicking the presence of new obscuring gas. Using the response of the ionized regions to the SED changes, we place constraints on their density and location., Comment: Accepted for publication in The Astrophysical Journal (ApJ), 15 pages, 5 figures

Photoionization modeling of active galactic nuclei (AGN) predicts that diffuse continuum (DC) emission from the broad-line region makes a substantial contribution to the total continuum emission from ultraviolet through near-infrared wavelengths. Evidence for this DC component is present in the strong Balmer jump feature in AGN spectra, and possibly from reverberation measurements that find longer lags than expected from disk emission alone. However, the Balmer jump region contains numerous blended emission features, making it difficult to isolate the DC emission strength. In contrast, the Paschen jump region near 8200 \r{A} is relatively uncontaminated by other strong emission features. Here, we examine whether the Paschen jump can aid in constraining the DC contribution, using Hubble Space Telescope STIS spectra of six nearby Seyfert 1 nuclei. The spectra appear smooth across the Paschen edge, and we find no evidence of a Paschen spectral break or jump in total flux. We fit multi-component spectral models over the range $6800-9700$ \r{A} and find that the spectra can still be compatible with a significant DC contribution if the DC Paschen jump is offset by an opposite spectral break resulting from blended high-order Paschen emission lines. The fits imply DC contributions ranging from $\sim$10% to 50% at 8000 \r{A}, but the fitting results are highly dependent on assumptions made about other model components. These degeneracies can potentially be alleviated by carrying out fits over a broader wavelength range, provided that models can accurately represent the disk continuum shape, Fe II emission, high-order Balmer line emission, and other components., Comment: 17 pages, 6 figures, and 3 tables; ApJ in press

The relation between warm absorber (WA) outflows of AGN and nuclear obscuration activities caused by optically-thick clouds (obscurers) crossing the line of sight is unclear. NGC 3227 is a suitable target to study the properties of both WAs and obscurers, because it matches the following selection criteria: WAs in both ultraviolet (UV) and X-rays, suitably variable, bright in UV and X-rays, good archival spectra for comparing with the obscured spectra. To investigate WAs and obscurers of NGC~3227, we used a broadband spectral-energy-distribution model built in our Paper I and the photoionization code of SPEX software to fit archival XMM-Newton and NuSTAR observations in 2006 and 2016. Using unobscured observations, we find four WAs with different ionization states (log$\xi$ [erg cm/s]~-1.0, 2.0, 2.5, 3.0). The highest-ionization WA has a higher hydrogen column density (~$10^{22}$/cm$^2$) than the other three WAs (~$10^{21}$/cm$^2$). Their outflow velocities range from 100 to 1300 km/s, and show a positive correlation with the ionization parameter. These WAs are estimated to be between the outer broad-line-region (BLR) and the narrow line region. Besides, we find an X-ray obscuration event in 2006, which was missed by previous studies. It can be explained by a single obscurer. We also study the previously published obscuration event in 2016, which needs two obscurers in the fit. A high-ionization obscurer (log$\xi$~2.80; covering factor $C_f$~30%) only appears in 2016, which has a high column density (~$10^{23}$/cm$^2$). A low-ionization obscurer (log$\xi$~1.0-1.9; $C_f$~20%-50%) exists in both 2006 and 2016, which has a lower column density (~$10^{22}$/cm$^2$). These obscurers are estimated to be in the BLR by their crossing time of transverse motions. The obscurers and WAs of NGC 3227 have different distances and number densities, which indicate that they might have different origins., Comment: 12 pages, 6 figures, 6 tables; accepted by A&A

We present the first results from the ongoing, intensive, multi-wavelength monitoring program of the luminous Seyfert 1 galaxy Mrk 817. While this AGN was, in part, selected for its historically unobscured nature, we discovered that the X-ray spectrum is highly absorbed, and there are new blueshifted, broad and narrow UV absorption lines, which suggest that a dust-free, ionized obscurer located at the inner broad line region partially covers the central source. Despite the obscuration, we measure UV and optical continuum reverberation lags consistent with a centrally illuminated Shakura-Sunyaev thin accretion disk, and measure reverberation lags associated with the optical broad line region, as expected. However, in the first 55 days of the campaign, when the obscuration was becoming most extreme, we observe a de-coupling of the UV continuum and the UV broad emission line variability. The correlation recovers in the next 42 days of the campaign, as Mrk 817 enters a less obscured state. The short CIV and Ly alpha lags suggest that the accretion disk extends beyond the UV broad line region., Comment: 28 pages, 14 figures, submitted to ApJ. Comments welcome

Outflows from active galactic nuclei (AGN) are one of the fundamental mechanisms by which the central supermassive black hole interacts with its host galaxy. Detected in $\ge 50\%$ of nearby AGN, these outflows have been found to carry kinetic energy that is a significant fraction of AGN power, and thereby give negative feedback to their host galaxies. To understand the physical processes that regulate them, it is important to have a robust estimate of their physical and dynamical parameters. In this review we summarize our current understanding on the physics of the ionized outflows detected in absorption in the UV and X-ray wavelength bands. We discuss the most relevant observations and our current knowledge and uncertainties in the measurements of the outflow parameters. We also discuss their origin and acceleration mechanisms. The commissioning and concept studies of large telescope missions with high resolution spectrographs in UV/optical and X-rays along with rapid advancements in simulations offer great promise for discoveries in this field over the next decade., Comment: An invited Review Article published in Nature Astronomy: https://www.nature.com/articles/s41550-020-01255-2

Determining the distance of quasar absorption outflows from the central source (R) and their kinetic luminosity are crucial for understanding their contribution to active galactic nucleus (AGN) feedback. Here we summarize the results for a sample of nine luminous quasars that were observed with the Hubble Space Telescope. We find that the outflows in more than half of the objects are powerful enough to be the main agents for AGN feedback, and that most outflows are found at R>100 pc. The sample is representative of the quasar absorption outflow population as a whole and is unbiased towards specific ranges of R and kinetic luminosity. Therefore, the analysis results can be extended to the majority of such objects, including broad absorption line quasars. We find that these results are consistent with those of another sample (seven quasars) that is also unbiased towards specific ranges of R and kinetic luminosity. Assuming that all quasars have absorption outflows, we conclude that most luminous quasars produce outflows that can contribute significantly to AGN feedback. We also discuss the criterion for whether an outflow is energetic enough to cause AGN feedback effects., Comment: 10 pages, 4 figures, accepted for publication in MNRAS

From Hubble Space Telescope/Cosmic Origins Spectrograph spectra of five quasars, 16 outflows are detected. For 11 outflows, we are able to constrain their distances to the central source (R) and their energetics. In instances of multiple electron number density determinations (used in the calculation of R) for the same outflow, the values are consistent within errors. For the 11 outflows, eight have measurements for R (between 10 and 1000 pc), one has a lower limit, another has an upper limit, and the last has a range in R. There are two outflows that have enough kinetic luminosity to be major contributors to active galactic nucleus feedback. The outflowing mass is found primarily in a very high-ionization phase, which is probed using troughs from, e.g., Ne VIII, Na IX, Mg X, and Si XII. Such ions connect the physical conditions of these ultraviolet outflows to the X-ray warm absorber outflows seen in nearby Seyfert galaxies. The ion Cl VII and several new transitions from Ne V have been detected for the first time., Comment: 29 pages, 3 figures, 4 tables, Accepted for publication in ApJS

We detect four very energetic outflows in the Hubble Space Telescope/Cosmic Origin Spectrograph spectra of quasar 2MASS J1051+1247 with a combined kinetic luminosity ($\dot{E_k}$) of 10$^{46}$ erg s$^{-1}$. Remarkable similarities are seen in these outflows: velocity centroids between 4900 and 5700 km s$^{-1}$, distances from the central source ($R$) of a few hundred parsecs that are all consistent within the errors, and an $\dot{E_k}$ within a factor of two for all outflows. Hence, a common origin for the outflows is probable. Most of the outflowing mass resides in a very high-ionization phase evident by troughs from Ne VIII, Na IX, Mg X, and Si XII, which connect the physical conditions of these ultraviolet outflows to the X-ray warm absorber outflows seen in nearby Seyfert galaxies. Three of the outflows have two or three independent diagnostics for the electron number density, yielding consistent values for each outflow, which increase the robustness of the $R$ determinations. Troughs from never-before-seen ionic transitions of Ar VI, O IV*, Ne VI*, and Ne V* are identified. With a combined $\dot{E_k}$ that is $7.0^{+6.5}_{-2.3}$ % of the quasar's Eddington luminosity, these outflows are prime candidates to be major agents for various active galactic nuclei feedback effects., Comment: 11 pages, 3 figures, 4 tables

We analyze absorption troughs from two outflows within PKS J0352-0711 (S1 at $-$1950 km s$^{-1}$ and S2 at $-$3150 km s$^{-1}$) from spectra taken with Hubble Space Telescope/Cosmic Origin Spectrograph, which cover the diagnostic-rich 585-900 Angstrom rest frame wavelength range. In S2, for the first time we clearly detect absorption troughs from Ca IV, Ca V, Ca V*, Ca VII*, and Ca VIII*. The column density measurement of Ca V suggests S2 has a super-solar metallicity. Both outflows require at least two ionization phases where the column density of the very high-ionization phase is roughly 15 times larger than the corresponding high-ionization phase. These high column densities and very high-ionization potential ions are similar to X-ray warm absorbers. The two phases of S2 show a unique velocity centroid shift between associated troughs. Through Monte Carlo measurements of the O V* absorption troughs, we determine the electron number density of S2 (fully corroborated by independent measurements from the Ca V* and Ca VIII* troughs), yielding a distance of 9 pc and a kinetic luminosity of 2$\times$10$^{43}$ erg s$^{-1}$. S1 is located farther away at 500 pc from the central source with a kinetic luminosity of 10$^{43}$ erg s$^{-1}$., Comment: 12 pages, 9 figures, 5 tables

The Hubble Space Telescope/Cosmic Origins Spectrograph (COS) has opened a new discovery space for studying quasar absorption outflows and their contribution to AGN feedback. Specifically, COS provides high-quality far-ultraviolet (FUV) spectra covering the diagnostic-rich 500-1050 Angstrom rest frame (hereafter, EUV500) of medium redshift objects. The quality and quantity of EUV500 diagnostic troughs allow us to probe the very high-ionization phase, which carries 90% or more of the outflowing material, as well as to determine the distance of most outflows from the central source ($R$). The first objective is impossible to achieve with ground-based spectra, and $R$ can be measured in only $\sim$1% of them. Here, we summarize the main results of the first dedicated survey of such outflows, including the following: 1) Measurements of the three most energetic outflows to date, which can be the main agents for AGN feedback processes in the environments of the host galaxies. 2) All the outflows have a very high-ionization component, similar to the one found in warm absorbers, which carries most of the outflow's kinetic luminosity. This finding suggests that all the high-ionization outflows observed from the ground also have a similar undetected very high-ionization component. 3) Of the 13 studied EUV500 outflows, 9 have $100

We present an analysis of the broad absorption line (BAL) velocity shift that appeared in one of the outflow systems in quasar SDSS J1042+1646. Observations were taken by the Hubble Space Telescope/Cosmic Origin Spectrograph in 2011 and 2017 in the 500 -- 1050 $\r{A}$ rest frame. The outflow's velocity centroid shifted by $\sim$ --1550 km s$^{-1}$ from --19,500 km s$^{-1}$ to --21,050 km s$^{-1}$ over a rest-frame time of 3.2 yr. The velocity shift signatures are most apparent in the absorption features from the Ne VIII $\lambda\lambda$ 770.41, 780.32 doublet and are supported by the absorption troughs from OV $\lambda$ 629.73 and the Mg X $\lambda\lambda$ 609.79, 624.94 doublet. This is the first time where a quasar outflow velocity shift is observed in troughs from more than one ion and in distinct troughs from a doublet transition (Ne VIII). We attribute the velocity shift to an acceleration of an existing outflow as we are able to exclude photoionization changes and motion of material into and out of the line of sight as alternate explanations. This leads to an average acceleration of 480 km s$^{-1}$ yr$^{-1}$ (1.52 cm s$^{-2}$) in the quasar rest frame. Both the acceleration and the absolute velocity shift are the largest reported for a quasar outflow to date. Based on the absorption troughs of the O V* multiplet, we derive a range for the distance of the outflow ($R$) from the central source, 0.05 pc $<$ $R$ $<$ 54.3 pc. This outflow shows similarities with the fast X-ray outflow detected in quasar PG 1211+143. We use the acceleration and velocity shift to constrain radiatively accelerated active galactic nucleus disk-wind models and use them to make predictions for future observations., Comment: 10 pages, 6 figures, published in ApJS

We present a study of the BAL outflows seen in quasar SDSS J1042+1646 (z = 0.978) in the rest-frame 500 -- 1050 $\r{A}$ (EUV500) region. The results are based on the analysis of recent Hubble Space Telescope/Cosmic Origins Spectrograph observations. Five outflow systems are identified, where in total they include $\sim$70 outflow troughs from ionic transitions. These include the first non-solar detections from transitions of O V*, Ne V*, Ar VI, Ca VI, Ca VII, and Ca VIII. The appearance of very high-ionization species (e.g., Ne VIII, Na IX, and Mg X) in all outflows necessitates at least two-ionization phases for the observed outflows. We develop an interactive Synthetic Spectral Simulation method to fit the multitude of observed troughs. Detections of density sensitive troughs (e.g., S IV* $\lambda$ 657.32 $\r{A}$ and the O V* multiplet) allow us to determine the distance of the outflows ($R$) as well as their energetics. Two of the outflows are at $R$ $\simeq$ 800 pc and one is at $R$ $\simeq$ 15 pc. One of the outflows has the highest kinetic luminosity on record ($\dot{E_{k}}$ $ = 5\times 10^{46}$ erg s$^{-1}$), which is 20% of its Eddington luminosity. Such a large ratio suggests that this outflow can provide the energy needed for active galactic nucleus feedback mechanisms., Comment: 18 pages, 12 figures, published in ApJS

We present the analysis of two outflows (S1 at --5500 km s$^{-1}$ and S2 at --9700 km s$^{-1}$) seen in recent HST/COS 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$\times$10$^4$ 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$\times$10$^3$ 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., Comment: 10 pages, 6 figures, published in ApJS

The highly energetic outflows from Active Galactic Nuclei detected in X-rays are one of the most powerful mechanisms by which the central supermassive black hole (SMBH) interacts with the host galaxy. The last two decades of high resolution X-ray spectroscopy with XMM and Chandra have improved our understanding of the nature of these outflowing ionized absorbers and we are now poised to take the next giant leap with higher spectral resolution and higher throughput observatories to understand the physics and impact of these outflows on the host galaxy gas. The future studies on X-ray outflows not only have the potential to unravel some of the currently outstanding puzzles in astronomy, such as the physical basis behind the MBH$-\sigma$ relation, the cooling flow problem in intra-cluster medium (ICM), and the evolution of the quasar luminosity function across cosmic timescales, but also provide rare insights into the dynamics and nature of matter in the immediate vicinity of the SMBH. Higher spectral resolution ($\le 0.5$ eV at $1$ keV) observations will be required to identify individual absorption lines and study the asymmetries and shifts in the line profiles revealing important information about outflow structures and their impact. Higher effective area ($\ge 1000 \rm \,cm^{2}$) will be required to study the outflows in distant quasars, particularly at the quasar peak era (redshift $1\le z\le 3$) when the AGN population was the brightest. Thus, it is imperative that we develop next generation X-ray telescopes with high spectral resolution and high throughput for unveiling the properties and impact of highly energetic X-ray outflows. A simultaneous high resolution UV + X-ray mission will encompass the crucial AGN ionizing continuum, and also characterize the simultaneous detections of UV and X-ray outflows, which map different spatial scales along the line of sight., Comment: A Science White Paper submitted to the Astro2020 Decadal Survey

The Seyfert Galaxy Mrk 335 is known for its frequent changes of flux and spectral shape in the X-ray band occurred during recent years. These variations may be explained by the onset of a wind that previous, non-contemporaneous high-resolution spectroscopy in X-ray and UV bands located at accretion disc scale. A simultaneous new campaign by XMM-Newton and HST caught the source at an historical low flux in the X-ray band. The soft X-ray spectrum is dominated by prominent emission features, and by the effect of a strong ionized absorber with an outflow velocity of 5-6X10$^3$~km~s$^{-1}$. The broadband spectrum obtained by the EPIC-pn camera reveals the presence of an additional layer of absorption by gas at moderate ionization covering 80% of the central source, and tantalizing evidence for absorption in the Fe~K band outflowing at the same velocity of the soft X-ray absorber. The HST-COS spectra confirm the simultaneous presence of broad absorption troughs in CIV, Ly alpha, Ly beta and OVI, with velocities of the order of 5000 km~s$^{-1}$ and covering factors in the range of 20-30%. Comparison of the ionic column densities and of other outflow parameters in the two bands show that the X-ray and UV absorbers are likely originated by the same gas. The resulting picture from this latest multi-wavelength campaign confirms that Mrk 335 undergoes the effect of a patchy, medium-velocity outflowing gas in a wide range of ionization states that seem to be persistently obscuring the nuclear continuum., Comment: 26 pages, 15 figures, accepted for publication on ApJ

We analyze new HST/COS spectra for two quasar absorption outflows seen in the quasi-stellar object LBQS 1206+1052. These data cover, for the first time, absorption troughs from $S_{IV}$, $Si_{II}$, and $P_V$. From the ratio of the $S_{IV}$* to $S_{IV}$ column densities, we measure the electron number density of the higher-velocity ($-1400$ km s$^{-1}$, v1400) outflow to be log($n_e$) = $4.23^{+0.09}_{-0.09}$ cm$^{-3}$ and constrain the lower-velocity ($-730$ km s$^{-1}$, v700) outflow to log($n_e$) $>$ $5.3$ cm$^{-3}$. The $n_e$ associated with the higher-velocity outflow is an order of magnitude larger than reported in prior work. We find that the previous measurement was unreliable since it was based on density-sensitive absorption troughs that were likely saturated. Using photoionization models, we determine the best $\chi^2$-minimization fit for the ionization parameter and hydrogen column density of the higher-velocity outflow: log($U_H$) = $-1.73^{+0.21}_{-0.12}$ and log($N_H$) = $21.03^{+0.25}_{-0.15}$ cm$^{-2}$, respectively. We calculate from $U_H$ and $n_e$ a distance of $500^{+100}_{-110}$ pc from the central source to the outflow. Using an SED attenuated by the v700 outflow yields a two-phase photoionization solution for the v1400 outflow, separated by a $\Delta U \approxeq 0.7$. Otherwise, the resultant distance, mass flux, and kinetic luminosity are similar to the unattenuated case. However, the attenuated analysis has significant uncertainties due to a lack of constraints on the v700 outflow in 2017., Comment: 11 pages, 6 figures, 4 tables, accepted for publication in ApJ

We observed the quasar PG1211+143 using the Cosmic Origins Spectrograph on the Hubble Space Telescope in April 2015 as part of a joint campaign with the Chandra X-ray Observatory and the Jansky Very Large Array. Our ultraviolet spectra cover the wavelength range 912-2100 A. We find a broad absorption feature (~1080 km/s) at an observed wavelength of 1240 A. Interpreting this as HI Ly alpha, in the rest frame of PG1211+143 (z=0.0809), this corresponds to an outflow velocity of -16,980 km/s (outflow redshift z_out ~ -0.0551), matching the moderate ionization X-ray absorption system detected in our Chandra observation and reported previously by Pounds et al. (2016). With a minimum HI column density of log N_HI > 14.5, and no absorption in other UV resonance lines, this Ly alpha absorber is consistent with arising in the same ultra-fast outflow as the X-ray absorbing gas. The Ly alpha feature is weak or absent in archival ultraviolet spectra of PG1211+143, strongly suggesting that this absorption is transient, and intrinsic to PG1211+143. Such a simultaneous detection in two independent wavebands for the first time gives strong confirmation of the reality of an ultra-fast outflow in an active galactic nucleus., Comment: Accepted for publication in the Astrophysical Journal, 12/23/2017

We present a detailed X-ray spectral study of the quasar PG 1211+143 based on Chandra High Energy Transmission Grating Spectrometer (HETGS) observations collected in a multi-wavelength campaign with UV data using the Hubble Space Telescope Cosmic Origins Spectrograph (HST-COS) and radio bands using the Jansky Very Large Array (VLA). We constructed a multi-wavelength ionizing spectral energy distribution using these observations and archival infrared data to create XSTAR photoionization models specific to the PG 1211+143 flux behavior during the epoch of our observations. Our analysis of the Chandra-HETGS spectra yields complex absorption lines from H-like and He-like ions of Ne, Mg and Si which confirm the presence of an ultra-fast outflow (UFO) with a velocity ~ $-$17,300 km s$^{-1}$ (outflow redshift $z_{\rm out}$ ~ $-$0.0561) in the rest frame of PG 1211+143. This absorber is well described by an ionization parameter $\log \xi$ ~ 2.9 erg s$^{-1}$ cm and column density $\log N_{\rm H}$ ~ 21.5 cm$^{-2}$. This corresponds to a stable region of the absorber's thermal stability curve, and furthermore its implied neutral hydrogen column is broadly consistent with a broad Ly$\alpha$ absorption line at a mean outflow velocity of ~ $-$16,980 km s$^{-1}$ detected by our HST-COS observations. Our findings represent the first simultaneous detection of a UFO in both X-ray and UV observations. Our VLA observations provide evidence for an active jet in PG 1211+143, which may be connected to the X-ray and UV outflows; this possibility can be evaluated using very-long-baseline interferometric (VLBI) observations., Comment: 17 pages, 10 figures, published in The Astrophysical Journal, proof corrections applied

Outflows in active galaxies (AGNs) are common, although their launching mechanism, location, and physical impact on the host galaxy remain controversial. We conducted a multiwavelength six-month campaign to observe the nearby Seyfert galaxy NGC 7469 with several observatories in order to better understand and quantify the outflow in this AGN. We report on the time-integrated line-resolved X-ray spectrum of NGC 7469 obtained with the Reflection Grating Spectrometer (RGS) on board XMM-Newton. We use the RGS spectrum to discern the many AGN outflow components. A global fit is applied to obtain their physical parameters. We find that the AGN wind can be well described by three narrow velocity components at -650, -950, and -2050 km/s. The RGS clearly resolves the -20 50 km/s component in C5+ Ly$\alpha$, while the -650 km/s and -950 km/s velocities are blended. Similar velocities are resolved in the UV. The H-equivalent column densities of these components are, respectively, NH = 7x10^20, 2.2x10^21, and 10^20 cm^-2, for a total of 3x10^21 cm^-2. The -650 km/s component shows a broad ionisation distribution. We identify a photo-ionised emission component blue-shifted by -450 km/s which we ascribe to the same outflow that produces the absorption lines. The elemental abundance ratios of C, N, Ne, S, and Fe to O in the outflow tend to be between 1 - 2 times solar. Preliminary estimates of the absorber distance from the AGN center suggest it is at least a few pc away from the center, but more advanced methods need to be applied in order to obtain better constraints. The complex X-ray spectrum of NGC 7469 demonstrates the richness of high energy phenomena taking place in AGN cores. The subtle spectroscopic differences between the various components require deep, high-resolution observations, such as the present RGS spectrum, if one is to resolve them and perform quantitative plasma diagnostics., Comment: To be published in A&A

We present results from a coordinated IR-to-X-ray spectral campaign of the QSO IRAS 13349+2438. Optical spectra reveal extreme Eigenvector-1 characteristics, but the H-beta line width argues against a NLS1 classification; we refine z=0.10853 based on [O III]. We estimate a BH mass=10^9 Msun using 2 independent methods (H-beta line width & SED fits). Blue-shifted absorption (-950km/s & -75km/s) is seen for the 1st time in STIS UV spectra from Ly-alpha, NV, & CIV. The higher velocity UV lines are coincident with the lower-ionisation (xi~1.6) X-ray warm absorber lines. A dusty multiple ionization absorber blueshifted by 700-900km/s is required to fit the X-ray data. Theoretical models comparing different ionising SEDs reveal that a UV-inclusive (i.e., the accretion disc) ionising continuum strongly impacts conclusions for the thermodynamic stability of the warm absorber. Specific to IRAS13349, an Xray-UV ionising SED favors a continuous distribution of ionisation states in a smooth flow (this paper), versus discrete clouds in pressure equilibrium (work by others where UV is omitted). Direct dust detections are seen in both the IR: PAH emission at (7.7 & 11.3)micron which may also be blended with forsterite, and (10 & 18)micron silicate emission, and X-rays: iron dust with a dust-to-gas ratio > 90%. We develop a geometrical model whereby the QSO nuclear region is viewed through the upper atmosphere of an obscuring torus. This sight line is obscured by dust that blocks a direct view of the UV/optical emission region but is largely transparent in X-rays since the gas is ionised. In our model, 20% of the intrinsic UV/optical continuum is scattered into our sight line by the far wall of an obscuring torus. An additional 2.4% of the direct light, which likely dominates the UV emission, is Thomson-scattered into our line-of-sight by another off-plane component of highly ionized gas., Comment: Accepted for publication to MNRAS 2013 January 8. Received 2013 January 7; in original form 2012 August 20. 31 MNRAS pages

The timing and duration of the reionization epoch is crucial to the emergence and evolution of structure in the universe. The relative roles that star-forming galaxies, active galactic nuclei and quasars play in contributing to the metagalactic ionizing background across cosmic time remains uncertain. Deep quasar counts provide insights into their role, but the potentially crucial contribution from star-formation is highly uncertain due to our poor understanding of the processes that allow ionizing radiation to escape into the intergalactic medium (IGM). The fraction of ionizing photons that escape from star-forming galaxies is a fundamental free parameter used in models to "fine-tune" the timing and duration of the reionization epoch that occurred somewhere between 13.4 and 12.7 Gyrs ago (redshifts between 12 > z > 6). However, direct observation of Lyman continuum (LyC) photons emitted below the rest frame \ion{H}{1} ionization edge at 912 \AA\ is increasingly improbable at redshifts z > 3, due to the steady increase of intervening Lyman limit systems towards high z. Thus UV and U-band optical bandpasses provide the only hope for direct, up close and in depth, observations of the types of environment that favor LyC escape. By quantifying the evolution over the past 11 billion years (z < 3) of the relationships between LyC escape and local and global parameters ..., we can provide definitive information on the LyC escape fraction that is so crucial to answering the question of, how did the universe come to be ionized? Here we provide estimates of the ionizing continuum flux emitted by "characteristic" (L_{uv}^*) star-forming galaxies as a function of look back time and escape fraction, finding that at z = 1 (7.6 Gyrs ago) L_{uv}^* galaxies with an escape fraction of 1% have a flux of 10^{-19} ergs cm^{-2} s^{-1} \AA^{-1}., Comment: Science white paper submitted to NASA Solicitation NNH12ZDA008L: Science Objectives and Requirements for the Next NASA UV/Visible Astrophysics Mission Concepts. 6 pages 4 figures - (abstract abridged)

There is unique and groundbreaking science to be done with a new generation of UV spectrographs that cover wavelengths in the "Lyman Ultraviolet" (LUV; 912 - 1216 Ang). There is no astrophysical basis for truncating spectroscopic wavelength coverage anywhere between the atmospheric cutoff (3100 Ang) and the Lyman limit (912 Ang); the usual reasons this happens are all technical. The unique science available in the LUV includes critical problems in astrophysics ranging from the habitability of exoplanets to the reionization of the IGM. Crucially, the local Universe (z <= 0.1) is entirely closed to many key physical diagnostics without access to the LUV. These compelling scientific problems require overcoming these technical barriers so that future UV spectrographs can extend coverage to the Lyman limit at 912 Ang., Comment: Science white paper submitted to NASA Solicitation NNH12ZDA008L: Science Objectives and Requirements for the Next NASA UV/Visible Astrophysics Mission Concepts. 6 pages PDF

Observing programs comprising multiple scientific objectives will enhance the productivity of NASA's next UV/Visible mission. Studying active galactic nuclei (AGN) is intrinsically important for understanding how black holes accrete matter, grow through cosmic time, and influence their host galaxies. At the same time, the bright UV continuum of AGN serves as an ideal background light source for studying foreground gas in the intergalactic medium (IGM), the circumgalactic medium (CGM) of individual galaxies, and the interstellar medium (ISM) and halo of the Milky Way. A well chosen sample of AGN can serve as the observational backbone for multiple spectroscopic investigations including quantitative measurements of outflows from AGN, the structure of their accretion disks, and the mass of the central black hole., Comment: Science white paper submitted to NASA Solicitation NNH12ZDA008L: Science Objectives and Requirements for the Next NASA UV/Visible Astrophysics Mission Concepts. 6 pages, 5 figures, PDF

We present analysis of the UV-spectrum of the low-z AGN IRAS-F22456-5125 obtained with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The spectrum reveals six main kinematic components, spanning a range of velocities of up to 800 km s-1, which for the first time are observed in troughs associated with CII, CIV, NV, SiII, SiIII, SiIV and SIV. We also obtain data on the OVI troughs, which we compare to those available from an earlier FUSE epoch. Column densities measured from these ions allow us to derive a well-constrained photoionization solution for each outflow component. Two of these kinematic components show troughs associated with transitions from excited states of SiII\ and CII. The number density inferred from these troughs, in combination with the deduced ioinization parameter, allows us to determine the distance to these outflow components from the central source. We find these components to be at a distance of ~ 10 kpc. The distances and the number densities derived are consistent with the outflow being part of a galactic wind., Comment: 52 pages, 15 figures, accepted for publication in ApJ March 25, 2012

Observations of He II Ly{\alpha} Gunn-Peterson troughs have proved to be a valuable probe of the epoch of helium reionization at z~3. Since this optical depth can become unmeasurably large even for modest He II fractions, various alternate techniques have been proposed to push to higher redshift, and among the more promising is looking at higher order Lyman-series troughs. We here report four new observations of the He II Ly{\beta} trough, including new data on the only sightline with a prior Ly{\beta} observation. However, the effective optical depth ratio {\tau}_eff,{\beta}/{\tau}_eff,{\alpha} is not simply predicted by (f_{\beta} {\lambda}_{\beta})/(f_{\alpha} {\lambda}_{\alpha})=0.16, and we analyze cosmological simulations to find that the correct ratio for helium at z~3 is ~0.35. In one case we infer {\tau}_eff,{\alpha} > 8.8, strong evidence that helium was not fully reionized at z=3.2--3.5, in agreement with previous measurements suggesting a later completion of reionization., Comment: ApJ accepted. 25 pages, 3 figures, 4 tables

We have produced the next generation of quasar spectral energy distributions (SEDs), essentially updating the work of Elvis et al. (1994) by using high-quality data obtained with several space and ground-based telescopes, including NASA's Great Observatories. We present an atlas of SEDs of 85 optically bright, non-blazar quasars over the electromagnetic spectrum from radio to X-rays. The heterogeneous sample includes 27 radio-quiet and 58 radio-loud quasars. Most objects have quasi-simultaneous ultraviolet-optical spectroscopic data, supplemented with some far-ultraviolet spectra, and more than half also have Spitzer mid-infrared IRS spectra. The X-ray spectral parameters are collected from the literature where available. The radio, far-infrared, and near-infrared photometric data are also obtained from either the literature or new observations. We construct composite spectral energy distributions for radio-loud and radio-quiet objects and compare these to those of Elvis et al., finding that ours have similar overall shapes, but our improved spectral resolution reveals more detailed features, especially in the mid and near-infrared., Comment: 46 pages, 10 figures, 10 tables, Accepted by ApJS. Composite SED data files for radio-loud and radio-quiet quasars (rlmsedMR.txt, rqmsedMR.txt) are included in the source (Other formats -> Source). Supplemental figures are not included