Disk-driven hydromagnetic winds as a key ingredient of active galactic nuclei unification schemes

Context. We present a study of the variability of the broad emission-line parameters of 3C390.3, an active galaxy with the doublepeaked emission-line profiles. We give a detailed analysis of the variation in the broad Hα and Hβ emission-line profiles, the ratios, and the Balmer decrement of different line segments. Aims. We explore the disk structure with an investigation of the variability of the broad-line profiles. This is assumed to emit the broad double-peaked Hβ and Hα emission lines in the spectrum of 3C390.3. Methods. We divided the observed spectra into two periods (before and after the outburst in 2002) and separately analyzed the variation in these two periods. First we analyzed the spectral emission-line profiles of the Hα and Hβ lines and measured the peak positions. Then, we divided the lines into several segments and measured the line-segment fluxes. The Balmer decrement variation for the entire Hα and Hβ fluxes and for the line segments was investigated and discussed. Additionally, we modeled the variations in the line parameters with an accretion disk model and compared our modeled line parameter variations with observed ones. Results. We compared the variability in the observed line parameters with the disk model predictions and found that the variation in line profiles and in the line segments corresponds to the emission of a disk-like broad-line region (BLR). But there is probably another additional emission component that contributes to the Hα and Hβ line center. We found that the variation in the line profiles is caused by the variation in the parameters of the disk-like BLR, first of all in the inner (outer) radius, which can well explain the line parameters variations in Period I. The Balmer decrement across the line profile has a bell-like shape and is affected not only by physical processes in the disk, but also by different emitting disk dimension of the Hα and Hβ line. Conclusions. The geometry of the BLR of 3C390.3 seems to be very complex, and inflows/outflows may be present, but evidently the broad-line region with its disk-like geometry is the dominant emitter.

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“…15 for the second half of the observing period. This behavior is consistent with the prediction from diskwind models (Königl & Kartje 1994).…”

Section: D Ccf Of the Hβ Line Profilessupporting

confidence: 91%

Spectral optical monitoring of 3C 390.3 in 1995–2007

Popovic

Shapovalova

Ilić

et al. 2011

A&A

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“…In this case we would have to assume a rather extended and filamentary medium in contrast to the simplified picture of spherically symmetric clouds bound by self-gravity. Mechanisms that are thought to be able to lead to these structures include MHD-driven winds that are launched from the accretion disk, for example, via magnetocentrifugally acceleration (Blandford & Payne 1982;Contopoulos & Lovelace 1994;Konigl & Kartje 1994). We find consistency between the measured ionization structure and column density of the absorber and the range of values simulated for MHD winds by Fukumura et al (2010).…”

Section: The Origin Of the Absorbersupporting

confidence: 67%

A variable-density absorption event in NGC 3227 mapped withSuzakuandSwift

Markowitz

Krauß

Miniutti

et al. 2015

A&A

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Context. The morphology of the circumnuclear gas accreting onto supermassive black holes in Seyfert galaxies remains a topic of much debate. As the innermost regions of active galactic nuclei (AGN) are spatially unresolved, X-ray spectroscopy, and in particular line-of-sight absorption variability, is a key diagnostic to map out the distribution of gas. Aims. Observations of variable X-ray absorption in multiple Seyferts and over a wide range of timescales indicate the presence of clumps/clouds of gas within the circumnuclear material. Eclipse events by clumps transiting the line of sight allow us to explore the properties of the clumps over a wide range of radial distances from the optical/UV broad line region (BLR) to beyond the dust sublimation radius. Time-resolved absorption events have been extremely rare so far, but suggest a range of density profiles across Seyferts. We resolve a weeks-long absorption event in the Seyfert NGC 3227. Methods. We examine six Suzaku and 12 Swift observations from a 2008 campaign spanning five weeks. We use a model accounting for the complex spectral interplay of three absorbers with different levels of ionization. We perform time-resolved spectroscopy to discern the absorption variability behavior. We also examine the IR to X-ray spectral energy distribution (SED) to test for reddening by dust. Results. The 2008 absorption event is due to moderately-ionized (log ξ ∼ 1.2-1.4) gas covering 90% of the line of sight. We resolve the density profile to be highly irregular, in contrast to a previous symmetric and centrally-peaked event mapped with RXTE in the same object. The UV data do not show significant reddening, suggesting that the cloud is dust-free. Conclusions. The 2008 campaign has revealed a transit by a filamentary, moderately-ionized cloud of variable density that is likely located in the BLR, and possibly part of a disk wind.

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“…Another explanation is that the absorbers are not simply radially (or even radiatively) accelerated. Disk-wind models (see, e.g., Konigl & Kartje 1994) require that the gas in the outflow must first be levitated off the accretion disk. Bottorff, Korista, & Shlosman (2000) have modeled the absorbers as part of a magnetohydromagnetic wind, which has a strong nonradial component.…”

Section: The Nature Of the Outflowmentioning

confidence: 99%

Variable Ultraviolet Absorption in the Seyfert 1 Galaxy NGC 3516: The Case for Associated Ultraviolet and X‐Ray Absorption

Kraemer

Crenshaw

George

et al. 2002

ApJ

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We present observations of the UV absorption lines in the Seyfert 1 galaxy NGC 3516, obtained at a resolution of =D % 40; 000 with the Space Telescope Imaging Spectrograph (STIS) on 2000 October 1. The UV continuum was $4 times lower than that observed during 1995 with the Goddard High Resolution Spectrograph (GHRS), and the X-ray flux from a contemporaneous Chandra X-Ray Observatory observation was a factor of $8 below that observed with ASCA. The STIS spectra show kinematic components of absorption in Ly , C iv, and N v at radial velocities of À376, À183, and À36 km s À1 (components 1, 2, and 3+4, respectively), which were detected in the earlier GHRS spectra; the last of these is a blend of two GHRS components that have increased greatly in column density. Four additional absorption components have appeared in the STIS spectra at radial velocities of À692, À837, À994, and À1372 km s À1 (components 5-8); these may also have been present in earlier low-flux states observed by the International Ultraviolet Explorer. Based on photoionization models, we suggest that the components are arranged in increasing radial distance in the order 3+4, 2, 1, followed by components 5-8. We have achieved an acceptable fit to the X-ray data using the combined X-ray opacity of the UV components 1, 2, and 3+4. By increasing the UV and X-ray fluxes of these models to match the previous high states, we are able to match the GHRS C iv column densities, the absence of detectable C iv absorption in components 5-8, and the 1994 ASCA spectrum. We conclude that variability of the UV and X-ray absorption in NGC 3516 is primarily due to changes in the ionizing flux.

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Disk-driven hydromagnetic winds as a key ingredient of active galactic nuclei unification schemes

Cited by 410 publications

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Spectral optical monitoring of 3C 390.3 in 1995–2007

Spectral optical monitoring of 3C 390.3 in 1995–2007

A variable-density absorption event in NGC 3227 mapped withSuzakuandSwift

Variable Ultraviolet Absorption in the Seyfert 1 Galaxy NGC 3516: The Case for Associated Ultraviolet and X‐Ray Absorption

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