Photoionization Modeling of Warm Absorbing Outflows in Active Galactic Nuclei

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Slide 1

Thank you for introduction I like to thank everyone for giving me the opportunity to come here to talk to you here. Today I am going to talk about photoionization modeling of warm absorbing outflows in AGN. I am working with Julia Lee at Harvard, Mike Nowak at MIT, Randall Smith at Smithsonian astrophysical observatory.

Slide 2

I would like to talk a bit about the warm aborbing outflow which recently found in X-ray observations of some AGNs in Seyfert I galaxies. I will start to talk a little about what is Seyfert 1 galaxies based on the AGN unified model developed over 2 decades ago. I'll talk about the different types of ionized absorbers, namely warm absrobers and ultra-fast outflow I will explain how we can determine the physical conditions of ionized abosrbers in AGN. I will explain the current status of ultra-fast outflows and warm absorber and a possible unification of these two phenomena based on a density profile of a single large scale outflow.

Slide 3

About 15% of nearby AGN (z <0.8) are classified as radio-load, in which source has strong-radio jets. About 85% of AGNs are classified as radio-quiet, which are separated into two groups: type 1 and type 2 Seyfert AGNs, in which it is difficult to find strong radio jets. Radio-load are divided into two groups: low-luminosity Fanaroff-Riely class I, and high-luminosity FR-II. FR-I shows a compact emission emerging from close to core. FR-II structure is dominated by the radio lobes and emission from the far end of the extended emission. Seyfert class is an optical classification first was introduced by Carl Seyfert in 1943. Seyfert I have broader narrow lines, bright in UV and X Seyfert II are bright in infrared, narrow forbidden line

Slide 4

In term of what we learn from X-ray spectroscopy of AGNs. We learned about thermal soft excess of accretion disk usually described by a black body, non-thermal hard excess of accretion disk typically described by a power-law. We learned about the presence of ionized abortion lines mainly in soft excess, and highly ionized Iron absorption lines in hard excess. These ionized aborbers emerge from several different zones in the AGN, and can be related to absorbing gas toward the line of sight. They always are blue-shifted, which could be related to outflows toward the line of sight in Seyfert I galaxies. We see highly Ionized absorbing outflows in X-ray spectrum which I am focusing today

Slide 5

There are two different types of ionized absorbers in X-ray observations: One of them is called warm absorbers, which are absorption lines in the soft X-ray band. Another one is called ultra-fast outflows are ionized Iron absorption line with velocities higher than 10,000 km/s. Warm Absorber, which are absorption lines of oxygen neon, magnesium, silicone, and sulfur, have been observed in nearly 60% of Syefert 1 galaxies. While ultra-fast outflows with velocities more than 10,000 km/s have been identified in 30% of radio-quiet and radio-load AGNs.

Slide 6

To study the physical properties of ionized absorber, we use photoionization modeling. There are two codes, which are commonly used in the X-ray astrophysics: XSTAR and CLOUDY. To model the X-ray spectrum of AGN, we use a phenomenological spectral model which include a soft excess black body, hard excess powerlaw, and a sum of photo-emission components and a product of absorption components. To produce these photo-emission and absorption components, one way is to use XSTARDB Another way is to use Parallelization of XSTAR PVM_XSTAR or MPI_XSTAR, which makes absorption and emission tables for a grid of parameters The typical parameters are: gas density, column density and ionization parameters

Slide 7

For photoionization modeling, we made an ionizing spectral energy distribution of PG 1211. We used our recent radio observation, archival optical and infrared, HST UV observation, and Chandra observation. Using this spectral energy distribution, we produce a grid of XSTAR tables in which the free parameters are: ionization parameter and column density. Here we see the Chandra spectrum fitted using multi component model. We identified several warm absorbers.

Slide 8

Fundamental parameters in photoionization modeling are the total hydrogen number density, the total hydrogen column density, and the ionization parameter. The ionization parameter in XSTAR is defined by this equation, L is the ionizing luminosity between 13.6 eV and 13.6 keV. R is distance from the ionizing source. The column density is also defined by this equation, where delta R is thickness of the ionized gaseous shell. A combination of these two equation can describe the upper limit of the shell, while the lower limit is given by this equation, which depends on the black hole mass, and maximum outflow velocity. Here, we see the typical ranges of fundamental parameters in a sample of AGNs: 42 radio-quiet, 51 AGN.

Slide 9

The density profile of these ionized outflows can be studied using the so-called absorption measure distribution, in the same way as emission measure distribution. The absorption measure distribution (AMD) is defined as the distribution of column density with ionization parameter. Assuming a power-law density profile described by the index alpha, from the AMD we can measure the power-law index alpha of the density profile. Behar found that the alpha is in the range of 1 to 1.3 in the 5 AGN. More recently Tombesi found the alpha of about 1.4 in 35 type 1 Seyfert AGNs, which means that the density has a power-law radial profile with radial slope of roughly 1.4.

Slide 10

The recent study of a sample of Seyfert I galaxies by Tombesi suggests that the ultra-fast outflows and the warm absorbers could be associated with different locations of a single large-scale outflow in the AGN. Here we see a linear correlation between the ionization parameter and the column density, as well as the outflow velocity. These linear correlations could be related to ionized X-ray absorbing layers of a single large-scale outflow along the line of sight, which has a power-law radial density profile. This schematic view suggests that the UFO is likely emerged from the inner zone, whereas the warm absorbers from outer zones.

Slide 11

Here is the summary of my talk. Just to conclude: Warm absorbers are detected in the sofat X-ray. Ultra fast outflow are those aborbers with speed higher than 10,000 km/s, and usually are iron H-like or He-like line. Using photoionization modeling, we can determine the physical conditions of ionized absorber, namely ionization paramters, column density, and gas density. Warm absorber and ultra-fast outflows could be associated with different layers of a single large-scale outflow with a powerlaw radial density profile. Our recent Chandra observation of PG1211 also suggest the presence of ultra-fast outflows in this quasar Thank you very much. I am happy to answer your questions.

Slide 15

Here we see a list of well-studied Seyfert galaxies with ionized absorbers. As you see ultra-fast outflows can be seen in those type I galaxies, and reach a mildly relativistic velocities of 0.1 to 0.2 of the speed of light, when they are blue-shifted. They even reach much higher velocity up to 0.4 c of the speed of light, when they are red-shifted. The blue-shifted lines are interpreted as outflows toward line of sight, wheres The red-shifted lines could be related to martial falling into the black hole.

Slide 1

Ashkbiz Danehkar Harvard-Smithsonian Center for Astrophysics ashkbiz.danehkar@cfa.harvard.edu October 7th, 2016 CfA Postdoc Symposium, Phillips Auditorium, Harvard/CfA/SAO, Cambridge , MA In collaborations with: Julia Lee (Harvard), Mike Nowak (MIT), Randall Smith (SAO), Gerard Kriss (STSI) and et al. Photoionization Modeling of Warm Absorbing Outflows in Active Galactic Nuclei PG 1211+143

Slide 2

October 7th, 2016 CfA Postdoc Symposium 2 Outline Introduction Active Galactic Nuclei Unified Model Ionized X-ray Absorbers in AGNs of Seyfert I Galaxies X-ray Ionized Absorbers Warm Absorbers (WAs) and Ultra-fast Outflows (UFOs) Photoionization Modeling of Ionized Absorbers Absorber Density Profile Unification of WAs and UFOs Conclusion

Slide 3

October 7th, 2016 CfA Postdoc Symposium 3 Introduction AGN Unified Model (radio-loud & -quiet AGN, Seyfert I & II Galaxies) Beckmann & Shrader 2012, Active Galactic Nuclei Unified Models for AFNs Antonucci, ARA&A, 1993, 31, 473 Unified Schemes for AGNs Megan Urry & Padovani, 1995, PASP, 107, 803 Fanaroff–Riley class I Fanaroff–Riley class II

Slide 4

October 7th, 2016 CfA Postdoc Symposium 4 Ionized X-ray Absorbers in AGNs of Seyfert I Galaxies Introduction Warm Absorbers Beckmann & Shrader 2012 (bbody + powerlaw + ∑ emis) x ∏ abs Hot Corona K-shell Iron Disk Black-body PG 1211+143

Slide 5

October 7th, 2016 CfA Postdoc Symposium 5 X-ray Ionized Absorbers Ultra-fast Outflows (UFOs): Highly Ionized absorption lines (primarily H-like & He-like Fe) with Velocity > 10,000 km/s (0.03c) high velocity ~ 0.1– 0.4c (Pounds + 2003, Cappi 2006, Braito + 2007) Recently observed in 30% of radio-quiet and -loud AGNs (Tombest + 2010,2011,2012,2014) “Warm” Absorbers (WAs): Ionized absorption lines (primarily H-like & He-like O, Ne, Mg, Si, S) with Velocity < 10,000 km/s (0.03c) Observed in 50% of Seyfert I galaxies (Reynold & Fabian 1995, Reynold 1997, George + 1998) PG 1211+143

Slide 6

October 7th, 2016 CfA Postdoc Symposium 6 XSTARDB & XSTAR2XSPEC Parallelization with MPI_XSTAR github.com/xstarkit/mpi_xstar Physical Conditions (free parameters): Column density (NH) Ionization parameter (ξ) Number density (n) Ionizing SED (Radio+UV+Opt+X-ray) Photoionization Modeling of Ionized Absorbers Photo-emission, Ionized absorption XSTAR (Kallman + 1996, 2004) or CLOUDY (Ferland + 1998) (bbody + powerlaw + ∑ photemis) x ∏ warmabs PG 1211+143

Slide 7

October 7th, 2016 CfA Postdoc Symposium 7 The Quasar PG 1211+143 Warm Absorber at -0.06c but further analysis needed PG 1211+143 Chandra Observations (PI J.C. Lee) PG 1211+143

Slide 8

October 7th, 2016 CfA Postdoc Symposium 8 Ionization parameter Photoionization Modeling of Ionized Absorbers Photoionization Code XSTAR (Kallman + 1996, 2004) Gas density Luminosity (0.0136-13.6 keV) Radius Column density Shell thickness Outflow velocity BH mass King & Pounds 2015; XMM-Newton & Suzaku (42 radio-quiet, Tombesi et al 2011; 51 AGN, Gofford et al. 2013)

Slide 9

October 7th, 2016 CfA Postdoc Symposium 9 Absorption Measure Distribution (AMD): similar to Emission Measure Distribution (EMD) Absorber Density Profile Tombesi + 2013 n(r) ~ r -1.4 density profile Behar 2009

Slide 10

October 7th, 2016 CfA Postdoc Symposium 10 Unification of UFOs and WAs Unification of X-ray Ionized Absorbers Tombesi + 2013

Slide 11

October 7th, 2016 CfA Postdoc Symposium 11 Summary Seyfert I galaxies WAs: X-ray absorption lines in soft excess (mainly H-like & He-like O, Ne, Mg, Si & S ions) with low velocity < 10,000 km/s UFOs: X-ray highly ionized absorption line (mainly H-like & He-like Fe) with high velocity higher than 10,000 km/s ~ 0.1– 0.4c Photoionization Code XSTAR (XSTAR Grids, xstardb) Physical Conditions: ionization parameters, column density, & gas density Absorber Density Profile: n(r) ~ r -1.4 Unification of X-ray Ionized Absorbers: UFOs + WAs ?

Slide 12

October 7th, 2016 CfA Postdoc Symposium 12 Thank you for your attention

Slide 13

October 7th, 2016 CfA Postdoc Symposium 13 XSTAR Grids log(NH) = 18 … 25 cm-2 log(ξ) = -3 … 5 log(n) = 12 cm-3 Vturb = fix (100 … 1000 km/s) Abundances = const. (solar) XSTAR2TABLE, XSTAR2XSPEC PVM_XSTAR (Noble et al 2009) Parallel Virtual Machine MPI_XSTAR Message Passing Interface xout_mtable.fits: absorption spectrum xout_ain.fits: emission spectrum Photoionization Modeling of Ionized Absorbers (bbody + powerlaw + ∑ emis) x ∏ abs xo01_detail.fits (pops.fits) xstardb in isis log(NH) = variable (18 … 25 cm-2) log(ξ) = variable (-3 … 5) log(n) = variable (11-14 cm-3) Vturb = variable Abundances = variables photemis() & warmabs() Photoionization Code XSTAR (Kallman et al 1996, 2004) (bbody + powerlaw + ∑ photemis) x ∏ warmabs PModel: PVM-based parallelization of ISIS models (bbody+powerlaw)*pm_mult(1,warmabs(1),warmabs(2))

Slide 14

October 7th, 2016 CfA Postdoc Symposium 14 Ionization parameter Photoionization Modeling of Ionized Absorbers Photoionization Code XSTAR (Kallman et al 1996, 2004) Gas density Luminosity (0.0136-13.6 keV) Radius Column density Shell thickness Outflow velocity BH mass (Haring & Rix 2004) σ = 4.4 (Kormendy & Ho 2013) King & Pounds 2015; XMM-Newton & Suzaku (Tombesi et al 2011; Gofford et al. 2013)

Slide 15

October 7th, 2016 CfA Postdoc Symposium 15 X-ray Ionized Absorbers Cappi 2006

Summary: CfA Postdoc Symposium, Harvard CfA, Cambridge, USA, October 7, 2016

Tags: active galactic nuclei warm absorbing outflows photoionization modeling

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