最近的高分辨率测量表明，模糊的射电银河系（RG）的软X射线光谱表现出的光电离气体（如3C 445和3C 33）的签名类似于在无线电安静模糊的活动星系核（AGN）中观察到的。虽然在附近的塞弗特1星系中，大约有一半的人口中发现了覆盖广泛温度和电离状态的温暖吸收气体的签名，但迄今为止，在宽线射电星系（BLRG）的高分辨率光谱中没有报道温暖吸收气体的痕迹。在这里，我们提出了第一次检测的软X射线温暖的吸收剂在强大的FRII BLRG 3C 382使用反射光栅光谱仪（RGS）上的XMM-牛顿。吸收气体似乎是高度电离的，柱密度约为10^{22} cm^{-2}，电离参数log γ>2 erg cm s^{-1}，流出速度约为10^{3} km s^{-1}。吸收线可能来自位于环面外部的区域，但距离小于60 pc。这一结果可能表明，以接近光速的速度喷射的等离子体和具有较慢流出速度的光电离气体可以在宽线区域之外的同一源中共存。
英文摘要：
Recent high-resolution measurements suggest that the soft X-ray spectrum of obscured Radio Galaxies (RG) exhibits signatures of photoionised gas (e.g. 3C 445 and 3C 33) similar to those observed in radio-quiet obscured Active Galactic Nuclei (AGN). While signatures of warm absorbing gas covering a wide range of temperature and ionisation states have been detected in about one half of the population of nearby Seyfert 1 galaxies, no traces of warm absorber gas have been reported to date in the high-resolution spectra of Broad Line Radio Galaxies (BLRG). We present here the first detection of a soft X-ray warm absorber in the powerful FRII BLRG 3C 382 using the Reflection Grating Spectrometer (RGS) on-board XMM-Newton. The absorption gas appears to be highly ionised, with column density of the order of 10^{22} cm^{-2}, ionisation parameter logξ>2 erg cm s^{-1} and outflow velocities of the order of 10^{3} km s^{-1}. The absorption lines may come from regions located outside the torus, however at distances less than 60 pc. This result may indicate that a plasma ejected at velocities near the speed of light and a photoionised gas with slower, outflow velocities can coexist in the same source beyond the Broad Line Regions.
Warm absorbers and related phenomena are one of the observable manifestations of outflows or winds from active galactic nuclei (AGN). Warm absorbers are common in low luminosity AGN, they have been extensively studied observationally, and are well described by simple phenomenological models. However, major open questions remain: What is the driving mechanism? What is the density and geometrical distribution? How much associated fully ionized gas is there? What is the relation to the quasi-relativistic 'ultrafast outflows' (UFOs)? In this paper we present synthetic spectra for the observable pr…
The Narrow-line Seyfert 1 galaxy NGC 4051 is known to exhibit significant X-ray spectral/flux variations and have a number of emission/absorption features. X-ray observations have revealed that these absorption features are blueshifted, which indicates that NGC 4051 has warm absorber outflow. In order to constrain physical parameters of the warm absorber outflow, we analyze the archival data with the longest exposure taken by XMM-Newton in 2009. We calculate the root-mean-square (RMS) spectra with the grating spectral resolution for the first time. The RMS spectra have a sharp peak and several…
The radiation from the central regions of active galactic nuclei, including that from the accretion disk surrounding the black hole, is likely to peak in the extreme ultraviolet $\sim 13 -100$ eV. However, due to Galactic absorption, we are limited to constrain the physical properties, i.e. the black hole mass and the accretion rate, from what observations we have below $\sim 10$ eV or above $\sim 100$ eV. In this paper we predict the thermal and ionization states of warm absorbers as a function of the shape of the unobservable continuum. In particular we model an accretion disk at $kT_{in} \s…
We report on the long- and short-term X-ray spectral analysis of the polar-scattered Seyfert 1.2 galaxy ESO 323-G77, observed in three epochs between 2006 and 2013 with Chandra and XMM-Newton. Four high-resolution Chandra observations give us a unique opportunity to study the properties of the absorbers in detail, as well as their short time-scale (days) variability. From the rich set of absorption features seen in the Chandra data, we identify two warm absorbers with column densities and ionisations that are consistent with being constant on both short and long time-scales, suggesting that th…
The aim of this paper is to study the variability of the warm absorber "clouds of ionised gas within AGN", for the Seyfert 1 galaxies Arakelian 564. The X-ray spectra for four XMM-Newton observations of this object are analysed in EPIC and RGS instruments. These four observations covered a period of eleven years. There are some changes in the ionisation parameter ($ ξ$) of the absorbing matter from one observation to another( $\logξ=0.889 \pm 3.11 \times 10^{-2}$ for year 2000 observation and $0.437 \pm 7.60 \times 10^{-2}$ for year 2001 ). Also the X-ray soft excess is studied for the four ob…
To investigate the origins of the warm absorbers in active galactic nuclei (AGNs), we study the ionization-state structure of the radiation-driven fountain model in a low-mass AGN (Wada et al. 2016) and calculate the predicted X-ray spectra, utilizing the spectral synthesis code Cloudy (Ferland et al. 2017). The spectra show many absorption and emission line features originated in the outflowing ionized gas. The O VIII 0.654 keV lines are produced mainly in the polar region much closer to the SMBH than the optical narrow line regions. The absorption measure distribution of the ionization param…
Warm absorbers are present in many Active Galactic Nuclei (AGN), seen as mildly ionised gas outflowing with velocities of a few hundred to a few thousand kilometres per second. These slow velocities imply a large launch radius, pointing to the broad line region and/or torus as the origin of this material. Thermal driving was originally suggested as a plausible mechanism for launching this material but recent work has focused instead on magnetic winds, unifying these slow, mildly ionised winds with the more highly ionised ultra-fast outflows. Here we use the recently developed quantitative mode…
Warm Absorbers (WAs), as an important form of AGN outflows, show absorption in both UV and X-ray band. Using XSTAR generated photoionization models, for the first time we present a joint fit to the simultaneous observations of HST/COS and Chandra/HETGS on NGC 3783. A total of five WAs explain well all absorption features from the AGN outflows, which are spread over a wide range of parameters: ionization parameter logξ from 0.6 to 3.8, column density log N_H from 19.5 to 22.3 cm^{-2}, velocity v from 380 to 1060 km s^{-1}, and covering factor from 0.33 to 0.75. Not all the five WAs are consiste…
We investigated, using spectral-timing analysis, the characterization of highly ionized outflows in Seyfert galaxies, the so-called warm absorbers. Here, we present our results on the extensive ~ 600 ks of XMM-Newton archival observations of the bright and highly variable Seyfert 1 galaxy NGC 4051, whose spectrum has revealed a complex multicomponent wind. Making use of both RGS and EPIC-pn data, we performed a detailed analysis through a time-dependent photoionization code in combination with spectral and Fourier spectral-timing techniques. The source light curves and the warm absorber parame…
We model the observed X-ray spectral continuum shape, ionic column densities, and absorption measure distribution (AMD) of the warm absorber in the Seyfert galaxy NGC 3783. We assume a photo-ionized medium with a uniform total (gas+radiation) pressure. The irradiation causes the wind to be radiation pressure compressed (RPC). We compare the observational characteristics derived from the 900 ksec Chandra observation to radiative transfer computations in pressure equilibrium using the radiative transfer code TITAN. We explore different values of the ionization parameter xi of the incident flux a…
Warm absorber (WA) is an ionised gas present in the line of sight to the AGN central engine. The effect of the absorber is imprinted in the absorption lines observed in X-ray spectra of AGN. In this work, we model the WA in Seyfert 1 galaxy Mrk 509 using its recently published shape of broad band spectral energy distribution (SED) as a continuum illuminating the absorber. Using the photoionization code {\sc Titan}, recently we have shown that the absorption measure distribution (AMD) found for this object can be successfully modelled as a single slab of gas in total pressure (radiation+gas) eq…
This paper is a sequel to the extensive study of warm absorber (WA) in X-rays carried out using high resolution grating spectral data from XMM-Newton satellite (WAX-I). Here we discuss the global dynamical properties as well as the energetics of the WA components detected in the WAX sample. The slope of WA density profile ($n\propto r^{-α}$) estimated from the linear regression slope of ionization parameter $ξ$ and column density $N_H$ in the WAX sample is $α=1.236\pm 0.034$. We find that the WA clouds possibly originate as a result of photo-ionised evaporation from the inner edge of the torus…
We report on the performance of the statistical, X-ray absorption lines identification procedure XLINE-ID. As illustration, it is used to estimate the time averaged gas density $n_H(r)$ of a representative AGN's warm absorber ($T\approx 10^5$~K) X-ray simulated spectrum. The method relies on three key ingredients: (1) a well established emission continuum level; (2) a robust grid of photoionisation models spanning several orders of magnitude in gas density ($n_H$), plasma column density ($N_H$), and in ionization states; (3) theoretical curves of growth for a large set of atomic lines. By comp…
Warm absorbers in X-rays (WAX), a comprehensive high resolution grating spectral study of a sample of Seyfert galaxies: I. A global view and frequency of occurrence of warm absorbers
我们提出的结果从均匀分析的宽带0.3-10 keV的CCD分辨率，以及软X射线高分辨率光栅光谱的硬X射线通量有限的样品26塞弗特星系观测XMM-牛顿。我们的目标是沿着活动核的视线来研究热吸收体（WA）的性质。我们在样本源的$65\%$中显著检测到WA。我们的研究结果是一致的WAs存在于至少一半的塞弗特星系在附近的宇宙中，与以前的估计。我们发现在$0.5<\logξ<1.5$的范围内，我们解释为WA云的热不稳定区域的电离参数的分布的差距。这可能表明，暖吸收流可能是由离散云的clusterical分布，而不是一个连续的介质。具有宽的Fe K $α$线的源的WA柱密度的分布类似于那些没有加宽的发射线的源。因此，检测到的宽Fe K $α$发射线是真实的，而不是软X射线中电离吸收的伪影。WA参数显示它们之间没有相关性，除了电离参数与柱密度。$\logξ$与$\log v_{\rm out}$线性回归（$0.12\pm 0.03$）的浅斜率与辐射或磁流体动力驱动风预测的标度律不一致。我们的研究结果还表明，WA和超快速外流（UFO）并不代表同一天体物理系统的极端表现。
We present the analysis of grating spectra of the Narrow Line Seyfert 1 Galaxy IRAS 17020+4544 observed by XMM-Newton in 2004 and 2014. In a previous work on these data, we reported the discovery of a multi-component ultra-fast outflow that is capable of producing feedback in the host galaxy. We also reported the presence of a slow, multi-phase warm absorber. In this follow-up paper, we confirm that this low velocity absorber can be modeled by four layers of ionized gas. When crossing our line-of-sight, this gas presents peculiar changes along the 10-yr time scale elapsed between the two obser…
We present new XMM-Newton observations of the intriguing warm absorber in I Zwicky 1. This luminous and nearby narrow-line Seyfert 1 galaxy shows ionized absorption by two components of outflowing gas; a low and a high-ionization phase with log $ξ$~0 and log $ξ$~2 respectively. Detailed modelling of these data reveal a complex and variable multi-phase warm absorber. However, we find the changes in the ionization state of the gas not to be straightforwardly correlated with the variability of the intrinsic continuum source, in apparent contrast with photoionization equilibrium. The observed vari…
Outflows of photoionized gas are commonly detected in the X-ray spectra of Seyfert 1 galaxies. However, the evidence for this phenomenon in broad line radio galaxies, which are analogous to Seyfert 1 galaxies in the radio-loud regime, has so far been scarce. Here, we present the analysis of the X-ray absorption in the radio-loud quasar 4C +74.26. With the aim of characterizing the kinetic and the ionization conditions of the absorbing material, we fitted jointly the XMM-Newton Reflection Grating Spectrometer (RGS) and the Chandra High Energy Transmission Grating Spectrometer (HETGS) spectra, w…
Ultra-thick warm absorbers: Enlarging the parameter space of AGN ionised outflows
INAF Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Space Science Data Center, Agenzia Spaziale Italiana（意大利航天局空间数据中心）；Center for Astrophysics | Harvard & Smithsonian（哈佛与史密森尼天体物理中心）；INAF – Osservatorio Astrofisico di Arcetri（意大利国家天体物理研究所阿切尔菲天文台）；ASI -Agenzia Spaziale Italiana（意大利航天局）；Dipartimento di Fisica, Università degli Studi di Roma Tor Vergata（罗马托维塔大学物理系）；INAF - Istituto di Astrofisica e Planetologia Spaziali（意大利国家天体物理研究所天体物理学与行星科学研究所）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）
During an extensive multiwavelength campaign that we performed in 2013-14 the prototypical Seyfert 1 galaxy NGC 5548 has been found in an unusual condition of heavy and persistent obscuration. The newly discovered "obscurer" absorbs most of the soft X-ray continuum along our line of sight and lowers the ionizing luminosity received by the classical warm absorber. Here we present the analysis of the high resolution X-ray spectra collected with XMM-Newton and Chandra throughout the campaign, which are suitable to investigate the variability of both the obscurer and the classical warm absorber. T…
Warm absorbers (WAs) located approximately in the region of $1-1000$ parsecs are common phenomena in many active galactic nuclei (AGNs). The driving mechanism of WAs is still under debate. Ultra-fast outflows (UFOs) which are launched very close to the central black hole are also frequently observed in AGNs. When UFOs move outwards, they will collide with the interstellar medius (ISM) gas. In this paper, we study the possibility that whether WAs can be generated by the interaction between ISM gas and the UFOs. We find that under some ISM gas conditions, WAs can be generated. However, the cover…
(Abridged) The archetypal Seyfert 1 galaxy NGC 5548 was observed in 2013-2014 in the context of an extensive multiwavelength campaign, which revealed the source to be in an extraordinary state of persistent heavy obscuration. We re-analyzed the archival grating spectra obtained by XMM-Newton and Chandra between 1999 and 2007 in order to characterize the classic warm absorber (WA) using consistent models and up-to-date photoionization codes and atomic physics databases and to construct a baseline model that can be used as a template for the WA in the 2013 observations. The WA in NGC 5548 is com…
In this paper we model the observed absorption measure distribution (AMD) in Mrk 509, which spans three orders of magnitude in ionization level with a single-zone absorber in pressure equilibrium. AMD is usually constructed from observations of narrow absorption lines in radio-quiet active galaxies with warm absorbers. We study the properties of the warm absorber in Mrk~509 using recently published broad-band spectral energy distribution observed with different instruments. This spectrum is an input in radiative transfer computations with full photoionisation treatment using {\sc titan} code. …
The properties of the clumpy torus and BLR in the polar-scattered Seyfert 1 galaxy ESO 323-G77 through X-ray absorption variability
我们报告的结果，从多历元X射线观测的极性散射塞弗特1星系ESO 323-G77。源表现出显着的光谱变化，从几个月到几年的时间尺度。所观察到的光谱变化完全是由于中性吸收体的柱密度朝向本征核连续谱的变化。柱密度通常是康普顿薄的，范围从几倍10 $^{22}$ cm $^{-2}$到几倍10 $^{23}$ cm $^{-2}$。然而，一个观测结果揭示了具有1.5 $\times$ 10 $^{24}$ cm $^{-2}$数量级的列密度的康普顿厚态。观测到的变化为研究活动星系中X射线吸收体的性质提供了难得的机会。我们从两个不同的组分中识别可变的X射线吸收，即（i）其单个团块具有$\leq$ 1.7 $\times$ 10 $^8$ cm $^{-3}$的密度和$\sim$ 4 $\times$ 10 $^{22}$ cm $^{-2}$的平均柱密度的团块，和（ii）宽线区（BLR），包括密度为0.1-8 $\times$ 10 $^9$ cm $^{-3}$和柱密度为10 $^{23}$-10 $^{24}$ cm $^{-2}$的单个云。推导出的clutterflorus的属性也可以用来估计环面半开角，这是47 $^\circ$的顺序。我们也证实了先前报道的检测两个高度电离的温暖的吸收器的流出速度为1000-4000公里秒$^{-1}$。观测到的外流速度与BLR处的开普勒/逃逸速度一…
Aims. We aim to investigate and characterise the photoionised X-ray emission line regions within NGC 7469. Methods. We apply the photoionisation model, PION, within the spectral fitting code SPEX to analyse the 640 ks RGS spectrum of NGC 7469 gathered during an XMM-Newton observing campaign in 2015. Results. We find the emission line region in NGC 7469 to be multiphased, consisting of two narrow components with ionisation parameters of $\log ξ= 0.4$ and 1.6. A third, broad emission component, with a broadening velocity of $v_b \sim 1400$ km s\textsuperscript{-1} and an outflow velocity of $v_{…
The narrow-line Seyfert 1 galaxy I Zwicky 1 shows a unique and complex system of ionised gas in outflow, which consists of an ultra-fast wind and a two-component warm absorber. In the last two decades, XMM-Newton monitored the source multiple times enabling the study of the long-term variability of the various outflows. Plasma in photoionisation equilibrium with the ionising source responds and varies accordingly to any change of the ionising luminosity. However, detailed modelling of the past RGS data has shown no correlation between the plasma ionisation state and the ionising continuum, rev…
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 photoionizati…
