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Related papers: The FeII Optical Emission in AGN

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We present the kinematical properties of the UV and optical \FeII\ emission gas based on the velocity shift and line width measurements of a sample of 223 Type 1 active galactic nuclei (AGNs) at 0.4 $<$ z $<$ 0.8. We find a strong…

Astrophysics of Galaxies · Physics 2020-01-08 Huynh Anh N. Le , Jong-Hak Woo

We present a study of FeII emission in the near-infrared region (NIR) for 25 active galactic nuclei (AGNs) to obtain information about the excitation mechanisms that power it and the location where it is formed. We employ a NIR FeII…

Astrophysics of Galaxies · Physics 2016-02-17 A. O. M. Marinello , A. Rodriguez-Ardila , A. Garcia-Rissmann , T. A. A. Sigut , A. K. Pradhan

We test the recent claim by Hu et al. (2008) that FeII emission in Type 1 AGN shows a systematic redshift relative to the local source rest frame and broad-line Hbeta. We compile high s/n median composites using SDSS spectra from both the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 J. W. Sulentic , P. Marziani , S. Zamfir , Z. Meadows

Recent JWST observations have revealed a large population of intermediate/low-luminosity AGN at early times with peculiar properties, different from local AGN or luminous quasars. To better understand the physical conditions in the BLRs of…

We obtained 0.8-2.4 micron spectra at a resolution of 320 km/s of four narrow-line Seyfert 1 galaxies in order to study the near-infrared properties of these objects. We focus on the analysis of the FeII emission in that region and the…

Astrophysics · Physics 2009-11-07 A. Rodriguez-Ardila , S. M. Viegas , M. G. Pastoriza , L. Prato

We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations of 10 unique sources. We present…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Xinwen Shu , Tahir Yaqoob , Junxian Wang

We investigate the spectral properties of the UV ($\lambda\lambda$2650-3050 \AA) and optical ($\lambda\lambda$4000-5500 \AA) Fe II emission features in a sample of 293 type 1 active galactic nuclei (AGNs) from Sloan Digital Sky Survey…

Astrophysics of Galaxies · Physics 2016-01-25 Jelena Kovacevic-Dojcinovic , Luka C. Popovic

It was suggested that the prominent feature of the optical Fe II emission has a connection with the accretion process in active galactic nuclei (AGN). For a large sample of 4037 quasars ($z < 0.8$) with measured $\rm H\beta$ line dispersion…

Astrophysics of Galaxies · Physics 2022-10-04 Liu Y. S. , Bian W. H.

In AGN spectra, a series of FeII multiplets form a pseudo-continuum that extends from the ultraviolet to the near-infrared (NIR). This emission is believed to originate in the Broad Line Region (BLR), and it has been known for a long time…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 A. Garcia-Rissmann , A. Rodriguez-Ardila , T. A. A. Sigut , A. K. Pradhan

We present the spectra of 14 quasars with a wide coverage of rest wavelengths from 1000 to 7300 A. The redshift ranges from z = 0.061 to 0.555 and the luminosity from M_{B} = -22.69 to -26.32. We describe the procedure of generating the…

We present near-infrared spectroscopy of the NLS1 galaxy PHL1092 (z=0.394), the strongest FeII emitter ever reported, combined with optical and UV data. We modeled the continuum and the broad emission lines using a power-law plus a black…

Astrophysics of Galaxies · Physics 2020-04-07 Murilo Marinello , Alberto Rodríguez-Ardila , Paola Marziani , Aaron Sigut , Anil Pradhan

Soft X-ray emission (0.5--2.0 keV) plays a pivotal role in regulating the optical and UV emission in the AGNs. We collected a sample of 1811 AGNs from the SDSS database and obtained various parameters of Balmer lines, optical continuum,…

High Energy Astrophysical Phenomena · Physics 2022-12-07 D. Nour , K. Sriram

We present a study of optical Fe II emission in 302 AGNs selected from the SDSS. We group the strongest Fe II multiplets into three groups according to the lower term of the transition (b $^4$F, a $^6$S and a $^4$G terms). These correspond…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Jelena Kovacevic , Luka C. Popovic , Milan S. Dimitrijevic

(Abridge) Near-infrared spectroscopy is used to study the kinematics and excitation mechanisms of the H2 and [FeII] gas in a sample of AGN. The H2 lines are unresolved in all objects in which they were detected while the [FeII] lines have…

We investigate FeII emission in Broad Line Region (BLR) of AGNs by analyzing the FeII(UV), FeII(4570) and MgII emission lines in 884 quasars in the Sloan Digital Sky Survey (SDSS) Quasar catalog in a redshift range of 0.727 < z < 0.804.…

Astrophysics of Galaxies · Physics 2015-05-19 H. Sameshima , K. Kawara , Y. Matsuoka , S. Oyabu , N. Asami , N. Ienaka

To find the spectral properties of AGNs in optical spectral band (around the Hb line) we constructed an Fe II template, that is covering Fe II emission from 4100 A to 5600 A. Using the new Fe II template we explored spectral properties of…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-09 Luka C. Popovic , Jelena Kovacevic , Milan S. Dimitrijevic

Understanding the Fe II emission from Active Galactic Nuclei (AGN) has been a grand challenge for many decades. The rewards from understanding the AGN spectra would be immense, involving both quasar classification schemes such as…

We review problems raised by Fe II emission in AGNs and address the question of its relationship to other broad-line region (BLR) lines. The self-shielding, stratified, BLR model of Gaskell, Klimek & Nazarova (2007; GKN) predicts that Fe II…

Astrophysics of Galaxies · Physics 2022-02-16 C. Martin Gaskell , Neha Thakur , Betsy Tian , Anjana Saravana

We study the FeII properties of double-peaked broad low-ionization emission line AGN (dbp emitters) using a sample of 27 dbp emitters from SDSS (DR4), with mean value $\sigma_{H\alpha_{B}}\sim3002\pm139{\rm km\cdot s^{-1}}$. Our first…

Astrophysics · Physics 2007-05-23 Xue-Guang Zhang , Dultzin-Hacyan Deborah , Ting-Gui Wang

[Latex markup removed] We recently discussed an Eigenvector 1 (E1) parameter space that provides optimal discrimination between the principal classes of broad-line Active Galactic Nuclei (AGN). In this paper we begin a search for the most…

Astrophysics · Physics 2009-11-06 P. Marziani , J. W. Sulentic , T. Zwitter , D. Dultzin-Hacyan , M. Calvani
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