Adi

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Accretion-disk outflows produce a wide variety of UV absorption lines in quasar spectra, from BALs and mini-BALs to narrow absorption lines (NALs) at speeds from ~0 to ~0.2c and velocity widths from ~10 to ~10,000 km/s. This diversity is critical to our understanding of the outflows. How are the different outflow features related? What can they tell us separately and altogether about the structure, origins, and energetics of quasar outflows? I will discuss several studies that address these questions using multi-epoch spectroscopy and Cloudy photoionization models of lines ranging from BALs to NALs. Our main goal is to derive basic outflow physical properties like the gas densities, total column densities, absorber locations, spatial sizes, and kinetic energies. We specifically examine low-abundance lines like PV 1118,1128 for column density constraints and excited-state lines like SiII*, CIII*, SIV*, HeI*, and FeII* combined with variability data for density and location constraints. I will also briefly describe a newly-discovered population of redshift z~2 extremely red quasars (ERQs) that has extreme outflow properties, perhaps during an early stage of quasar-galaxy evolution.

The most robust way for determining the distance of quasar absorption outflows is the use of troughs from excited states. Here we report the results of two surveys targeting outflows that show troughs from S iv. One survey includes 1091 SDSS and BOSS quasar spectra, and the other includes much higher quality spectra of 13 quasar observed with the Very Large Telescope. We demonstrate that the depth ratio of S iv* to S iv troughs is a powerful diagnostic for the distance of the outflows from the central source. Since S iv is formed in the same physical region of the outflow as the canonical outflow-identifying species Civ, the results of these surveys are applicable to the large majority of quasar outflows. We find that at least 50% of quasar outflows are at distances larger than 100 parsecs from the central source, and at least 12% are at distances larger than 1000 parsecs. These results have profound implications to the study of the origin and acceleration mechanism of quasar outflows, and their effects on the host galaxy.

Questions regarding empirical methods of determining the distance of quasar outflows from the central source.

1. What Methods are currently used?
2. What is their ranking of reliability, as far as model-dependency, assumption that need to be made, and anything else that impact the robustness of the derived distances.
3. Do we have robust empirical evidence for quasar outflows situated at distances much smaller than 1 pc. from the central source?

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I will describe results from a large-scale, and still growing, spectroscopic survey of multi-year ultraviolet broad absorption line (BAL) variability in ~ 2100 quasars. This survey is primarily based on spectra from the ongoing Sloan Digital Sky Survey (SDSS) and is about two orders of magnitude larger than past comparable surveys – it is helping to transform the field of multi-year BAL variability studies into one that supplies robust statistical constraints that can effectively guide models of quasar winds and their feedback. Additional multiwavelength observations (primarily in the X-ray band) have been obtained to complement the SDSS spectra when important. This large-scale BAL variability survey allows novel studies of, e.g., disappearing and emerging BALs, coordinated BAL-trough variations, BAL acceleration/deceleration, BAL vs. emission-line variability, unusually stable BALs, and redshifted BAL profile variability. I will present some of the main survey results along with resulting open questions for discussion.

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• What are the connection(s) between outflows seen in X-ray absorption, in UV absorption, and at longer wavelengths?
• How do accretion structures (thin/slim/thick disk; chaotic cold accretion; etc.) depend on physical parameters?
• What impact do different accretion structures have on outflows?
• How important are continuum, line, and MHD driving to accelerating outflows?
• What signatures of wind acceleration should we look for (in X-rays, in the UV, etc)?
• What can continuum and absorption variability tell us about source and outflow properties and structure (e.g., will rotation + azimuthal asymmetries lead to UV absorption trough variability)?
• What are typical rates of mass, momentum, and kinetic energy loss via outflows?

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We present recent results on the kinematics of the narrow-line regions (NLRs) in nearby Seyfert galaxies based on observations with the Gemini Near Infrared

Field Spectrometer (NIFS), obtained in the Z, J, and K bands at an angular resolution of ~0.1″ and a spectral resolving power of ~5000. We find strong evidence for in situ radiative driving of ionized gas away from molecular gas/dust spirals that enter the AGN ionizing bicone within ~1 kpc of the supermassive black hole (SMBH). We also detect outflowing warm molecular (H_2) gas inside of ~1 kpc after subtraction of the stellar velocity field from the CO bandheads. Our long-slit spectra from the Apache Point Observatory 3.5-meter telescope show that the AGN-ionized gas is typically dominated by rotation beyond ~1 kpc from the central SMBH and often extends out to at least several kpc , defining the extended NLR (ENLR). The NLR outflows in these moderate-luminosity AGN may not be sufficient to evacuate their entire bulges.

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Joint consideration of X-ray timing data in conjunction with time resolved spectroscopy allows us to detect and interpret lags within the X-ray band and thus tackle several key questions in AGN research, i.e.   

1. what is the origin of the time lags between different X-ray bands  
2. what are the distance, global covering, physical state, velocity and mass of the X-ray reprocessing gas 

AND

3. what constraints can be obtain on the X-ray reprocessor from observations in other wavebands.

I consider results from existing X-ray data, and pose the question as to what new observations would be most valuable for forward progress, using existing available satellites. 

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The talk will describe the wealth of information that can be extracted from the broad ionization distribution of Seyfert outflows.

We will try to address the following key questions

• Is the outflow one physical entity, or is it a collection of individual components (e.g., clouds)
• Is the outflow compact or extended over multi-pc scales
• How do the general features of radiation, thermal, and magnetic driving compare with X-ray spectra of Seyfert outflows

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In this contribution I give an overview on detections of X-ray obscuration in AGN.  First I present the discovery of obscuration in NGC 5548. In particular the simultaneous presence of lowly ionized, high column density X-ray absorption together with the presence of broad, deep absorption troughs in the UV allowed us to obtain a consistent picture of what is happening during this process. I will indicate some of the challenges in the spectral modeling of these data. Obscuration has also been found in a couple of other sources, and I will briefly compare the similarities and differences between the obscuration in these sources. I finish with some open questions. like:

• what is the difference between obscuration and an eclipse?
• What are the timescales for obscuration: weeks, years, centuries?
• where is the obscuring stream originally born and how?
• is there a connection between certain accretion disk behavior and the obscuration?
• What fraction of the AGN continuum is covered by the obscuration?

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Starting from recent X-ray studies of sizable samples of local Seyfert galaxies at moderate and high energy resolution, I will address the following questions:         

• Are the distributions of AGN wind physical parameters dependent on AGN luminosity or radio-loudness?
• How complete is our census of AGN winds? How many of them are we missing due to ionisation or inclination (or other) effects?
• UFOs in the post-Hitomi era: are we still seeking for an ultimate observational confirmation? Do observations of UFOs at high energy resolution support the finding at moderate (CCD) resolution?
• “Warm absorbers” vs. UFOs: two populations? Two aspects of the same underlying phenomenon?
• Are the different observational components of AGN outflows part of the same stratified flow? Are they independent components launched at different scales?
• What does the “ionisation gap” mean?
• Which observational constraints exist on the mechanism launching and accelerating the winds?
• Do AGN outflows contribute (or are responsible) for AGN obscuration?
• How uncertain are our estimates of mass/kinetic energy/momentum outflow rates?
• Bonus question (depending on the XRM status):
• Should XRM (X-Ray Re-flight Mission) fly, would the AGN wind observation plan originally designed for Hitomi still be adequate?