XMM/HST monitoring of the ultra-soft highly accreting Narrow Line Seyfert 1 RBS 1332
R. Middei, S. Barnier, F. G. Saturni, F. Ursini, P. -O. Petrucci, S. Bianchi, M. Cappi, M. Clavel, B. De Marco, A. De Rosa, G. Matt, G. A. Matzeu, M. Perri
超软窄线赛弗特1型星系（US-NLSy）是一类观测不足的活动星系核，其特征是显著的流量变化和极端的软X射线超。这种奇特的光谱形态为检验通常用于建模近邻AGN的标准框架是否仍然有效提供了黄金机会。因此，我们展示了对高吸积率US-NLSy RBS 1332开展的XMM-Newton与HST联合监测活动的结果。RBS 1332的光学至紫外光谱显示出分层窄线区和电离外流的证据，该外流在若干高电离跃迁（Lyα、N V、C IV）中产生速度范围很广（从约1500 km s⁻¹到约1700 km s⁻¹）的吸收槽。从光谱角度看，该源的光学/紫外/FUV/X射线辐射由三个不同成分叠加而成，这些成分在双冕框架下得到最佳建模；在该框架中，RBS 1332的辐射可归因于标准外盘、暖康普顿化区域和软冕连续谱。当前数据集与纯相对论反射情景不兼容。最后，采用新模型 reXcor 使我们能够确定，RBS 1332中的软X射线超主要由光厚、暖康普顿化介质的发射主导，而来自灯柱状冕的相对论反射预计仅有边际贡献。
英文摘要：
Ultra-soft narrow line Seyfert 1 (US-NLSy) are a poorly observed class of active galactic nuclei characterized by significant flux changes and an extreme soft X-ray excess. This peculiar spectral shape represents a golden opportunity to test whether the standard framework commonly adopted for modelling local AGN is still valid. We thus present the results on the joint XMM-Newton and HST monitoring campaign of the highly accreting US-NLSy RBS 1332. The optical-to-UV spectrum of RBS 1332 exhibits evidence of both a stratified narrow-line region and an ionized outflow, that produces absorption troughs over a wide range of velocities (from ~1500 km s-1 to ~1700 km s-1) in several high-ionization transitions (Lyalpha, N V, C IV). From a spectroscopic point of view, the optical/UV/FUV/X-rays emission of this source is due to the superposition of three distinct components which are best modelled in the context of the two-coronae framework in which the radiation of RBS 1332 can be ascribed to a standard outer disk, a warm Comptonization region and a soft coronal continuum. The present dataset is not compatible with a pure relativistic reflection scenario. Finally, the adoption of the novel model reXcor allowed us to determine that the soft X-ray excess in RBS 1332 is dominated by the emission of the optically thick and warm Comptonizing medium, and only marginal contribution is expected from relativistic reflection from a lamppost-like corona.
The jet in active galactic nuclei (AGN) is a key ingredient in understanding the co-evolution of galaxies and their central supermassive black holes (SMBHs). Unfortunately, the mechanism of jet launching and collimation is still elusive. The observational evidence of decreasing radio loudness with increasing Eddington ratio implies that the jet should be coupled with the accretion process. To further explore the relationship between the jet and accretion, it is necessary to extend our knowledge of the jet to an extreme end of the Eddington ratio distribution of AGN. Using Very Long Baseline Ar…
This study aims at identifying luminous quasars at $z>5.7$ among X-ray-selected sources in the eROSITA Final Equatorial-Depth Survey (eFEDS) in order to place a lower limit on black hole accretion well into the epoch of re-ionisation. We confirm the low significance detection with eROSITA of a previously known, optically faint $z=6.56$ quasar from the Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs) survey. We obtained a pointed follow-up observation of the source with the Chandra X-ray telescope in order to confirm the eROSITA detection. Using new near-infrared spectroscopy, we d…
The physical properties of the accretion flow and of the X-ray emitting plasma, in supermassive black holes accreting at extreme Eddington rates, are still very unclear. Here we present the analysis of simultaneous XMM-Newton and NuSTAR observations of the hyper-Eddington Seyfert 1 galaxy IRAS 04416+1215, carried out in 2020. The main goal of these observations is to investigate the properties of the X-ray corona, as well as the structure of the accretion flow and of the circumnuclear environment, in this regime of extreme accretion. IRAS 04416+1215 has one of the highest Eddington ratio ($λ_{…
Active galactic nuclei (AGN) are powered by accreting supermassive black holes, surrounded by a torus of obscuring material. Recent studies have shown how the torus structure, formerly thought to be homogeneous, appears to be 'patchy': the detection of variability in the line-of-sight hydrogen column density, in fact, matches the description of an obscurer with a complex structure made of clouds with different column density. In this work, we perform a multi-epoch analysis of the X-ray spectra of the Seyfert 2 galaxy NGC 7479 in order to estimate its torus properties, such as the average colum…
CSS J102913+404220 is a peculiar narrow line Seyfert 1 galaxy with an energetic nuclear optical outburst. We present a detailed analysis of its multi-wavelength photometric and spectroscopic observations covering a period of decade since outburst. We detect mid-infrared (MIR) flares delayed by about two months relative to the optical outburst, with an extremely high peak luminosity of log(L_4.6um)>44 erg/s. The MIR peak luminosity is at least an order of magnitude higher than any known supernovae explosions, suggesting the optical outburst might be due to a stellar tidal disruption event (TDE)…
I Zwicky 1 is the prototype optical narrow line Seyfert 1 galaxy. It is also a nearby ($z=0.0611$), luminous QSO, accreting close to the Eddington limit. XMM-Newton observations of I Zw 1 in 2015 reveal the presence of a broad and blueshifted P-Cygni iron K profile, as observed through a blue-shifted absorption trough at 9 keV and a broad excess of emission at 7 keV in the X-ray spectra. The profile can be well fitted with a wide angle accretion disk wind, with an outflow velocity of at least $-0.25c$. In this respect, I Zw 1 may be an analogous to the prototype fast wind detected in the QSO, …
To quantify the role of radio jets for Intra-Night Optical Variability (INOV) in Radio-Loud Narrow-Line Seyfert 1 (RLNLSy1) galaxies, we report the first systematic comparative INOV study of 23 RLNLSy1 galaxies, with 15 RLNLSy1s having confirmed detection of jets (jetted) and the remaining 8 RLNLSy1s having no detection of jets (non-jetted) based on their Very Long Baseline Array observations. We have monitored these two samples, respectively, in 37 and 16 sessions of a minimum 3-hour duration each. Based upon F$^η$-test at 99\% confidence level with a typical INOV amplitude ($ψ$) detection th…
How similar are narrow-line Seyfert 1 galaxies and high-z type 1 AGN?
European Southern Observatory (ESO)（欧洲南方天文台）；Texas Tech University（德克萨斯理工大学）；INAF - Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Universidad Diego Portales（迭戈帕托莱斯大学）
We report the discovery of extreme X-ray variability in a type 1 quasar: SDSS J$075101.42+291419.1$. It has a black hole mass of $1.6\times 10^7~\rm M_\odot$ measured from reverberation mapping (RM), and the black hole is accreting with a super-Eddington accretion rate. Its XMM-Newton observation in 2015 May reveals a flux drop by a factor of $\sim 22$ with respect to the Swift observation in 2013 May when it showed a typical level of X-ray emission relative to its UV/optical emission. The lack of correlated UV variability results in a steep X-ray-to-optical power-law slope ($α_{\rm OX}$) of -…
Narrow-Line Seyfert 1 (NLS1) Galaxies are an important type of active galactic nucleus (AGN), generally expected to be accreting at high Eddington rate. The properties of their outflows and importance of AGN feedback remain intriguing. We report on the discovery of fast outflowing warm absorbers (WAs) in the NLS1 PG 1001+054, with velocities in the range of 7000 to 9000 kilometers per second. They are identified with blueshifted Lyman alpha, N v and Si iv lines in the high resolution ultraviolet (UV) spectra taken with the Cosmic Origins Spectrograph (COS) onboard the Hubble Space Telescope (H…
A Changing-Look Seyfert Discovered by eROSITA Reveals a Two-Component Broad-Line Region
Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences（波兰科学院 Nicolaus Copernicus 天文学中心）；Leibniz-Institut für Astrophysik Potsdam (AIP)（波茨坦莱布尼茨天体物理研究所 (AIP)）；Institute of Astronomy, University of Cambridge（剑桥大学天体物理研究所）；Center for Theoretical Physics, Polish Academy of Sciences（波兰科学院理论物理中心）；Astronomical Observatory, University of Warsaw（华沙大学天文台）；Department of Physics, University of Johannesburg（约翰内斯堡大学物理系）；Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander Universität Erlangen-Nürnberg（弗里德里希·阿列克桑德埃尔朗根-纽伦堡大学 Dr. Karl Remeis 天文台和埃尔朗根天体粒子物理中心）；Inter-University Centre for Astronomy and Astrophysics（跨大学天文学与天体物理学中心）；South African Astronomical Observatory（南非天文台）；Department of Astronomy, University of Cape Town（开普敦大学天文学系）；Department of Physics, University of the Free State（自由邦大学物理系）；Universität Potsdam（波茨坦大学）；Department of Physics and Astronomy, University of North Carolina at Chapel Hill（北卡罗来纳大学教堂山分校物理与天文学系）；Max-Planck-Institut für Extraterrestrische Physik（马克斯·普朗克地外物理研究所）
Variable X-ray reverberation in the rapidly accreting AGN Ark 564: the response of the soft excess to the changing geometry of the inner accretion flow
We present the multi-epoch monitoring with NuSTAR and XMM-Newton of NGC 1358, a nearby Seyfert 2 galaxy whose properties made it a promising candidate X-ray changing look AGN, i.e., a source whose column density could transition from its 2017 Compton-thick (CT-, having line-of-sight Hydrogen column density NH,los>10^24 cm^-2) state to a Compton-thin (NH,los<10^24 cm^-2) one. The multi-epoch X-ray monitoring confirmed the presence of significant NH,los variability over time-scales as short as weeks, and allowed us to confirm the "changing look" nature of NGC 1358, which has most recently been o…
