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Related papers: Panchromatic Properties of the Extreme FeII Emitte…

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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 theoretical FeII emission line strengths for physical conditions typical of Active Galactic Nuclei with Broad-Line Regions. The FeII line strengths were computed with a precise treatment of radiative transfer using extensive and…

Astrophysics · Physics 2009-11-07 T. A. A. Sigut , Anil K. Pradhan

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 have calculated FeII emission line strengths for Active Galactic Nuclei Broad-Line Regions using precise radiative transfer and Iron Project atomic data. We improve the treatment of all previously considered excitation mechanisms for the…

Astrophysics · Physics 2009-10-30 T. A. A. Sigut , Anil K. Pradhan

This paper reports the results of a near infrared spectroscopic survey of LINER galaxies undertaken with a new infrared spectrograph at the 5 m Hale telescope. The galaxy sample includes 11 LINERs with spectra covering the [FeII] (1.2567…

Astrophysics · Physics 2009-10-30 J. E. Larkin , L. Armus , R. A. Knop , B. T. Soifer , K. Matthews

We investigated the optical FeII emission in a sample of about 215 low-redshift AGN (quasars and luminous Seyfert 1 galaxies). We find that a scaled and broadened FeII template based on the I Zw 1 spectrum can satisfactorily model the FeII…

Astrophysics · Physics 2007-05-23 C. Bongardo , R. Zamanov , P. Marziani , M. Calvani , J. W. Sulentic

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

One of the puzzles in understanding the spectra of active galactic nuclei (AGN) is the origin of the FeII emission. FeI emission, if present, will help reveal the physical conditions of the emitting gas. In an attempt to verify the presence…

Astrophysics · Physics 2009-10-22 John Kwan , Fu-zhen Cheng , Li-Zhi Fang , Wei Zheng , Jian Ge

We present new near-infrared (rest-frame UV-to-optical) spectra of the high redshift, gravitationally lensed quasar B 1422+231 (z=3.62). Diagnostic emission lines of FeII, [OIII]5007, and Hb, commonly used to determine the excitation,…

Astrophysics · Physics 2009-10-31 T. Murayama , Y. Taniguchi , A. S. Evans , D. B. Sanders , K. -W. Hodapp , K. Kawara , N. Arimoto

The work initially started as a test to retrace the Shen & Ho (2014) Quasar Main Sequence diagram where they claimed that the parameter RFeII, which defines the Eigenvector 1 (EV1) is driven by the Eddington ratio alone. We subsequently…

High Energy Astrophysical Phenomena · Physics 2020-06-17 Swayamtrupta Panda , Katarzyna Małek , Marzena Śniegowska , Bożena Czerny

X-shooter and ISIS WHT spectra of the starforming galaxy PHL 293B also known as A2228-00 and SDSS J223036.79-000636.9 are presented in this paper. We find broad (FWHM = 1000km/s) and very broad (FWZI = 4000km/s) components in the Balmer…

Astrophysics of Galaxies · Physics 2015-06-22 R. Terlevich , E. Terlevich , G. Bosch , A. I. Diaz , G. Hagele , M. Cardaci , V. Firpo

This is the second of two papers reporting observations and analysis of the unusually bright (m_b=14.4), luminous (M_B=-25.5), nearby (z=0.192) narrow-line quasar PHL 1811. The first paper reported that PHL 1811 is intrinsically X-ray weak,…

Astrophysics · Physics 2019-08-19 Karen M. Leighly , Jules P. Halpern , Edward B. Jenkins , Darrin Casebeer

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 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

A ROSAT observation of the narrow-line Fe II QSO PHL 1092 shows rapid variability that requires an efficiency of at least 0.13, exceeding the theoretical maximum for an accretion disk around a non-rotating black hole. Plausible explanations…

Astrophysics · Physics 2009-10-28 Karl Forster , Jules P. Halpern

We present near-infrared spectra with resolutions of lambda/dlambda~1200 in the emission lines of Pa-beta, [FeII] (1.2567um), Br-gamma, and H2 v=1-0S(1) of the nuclei and circumnuclear regions of the four Seyfert 2 galaxies Mk 1066, NGC…

Astrophysics · Physics 2009-11-06 R. A. Knop , L. Armus , K. Matthews , T. W. Murphy , B. T. Soifer

The aim of this work is to identify HeII emitters at 2<z<4.6 and to constrain the source of the hard ionizing continuum that powers the HeII emission. We have assembled a sample of 277 galaxies with a high quality spectroscopic redshift at…

We present a high S/N spectrum for the quasar PG 1138+222. We detect a very broad HeII$\lambda$4686 emission line component with twice the FWHM of the conventional broad line region (BLR) as evidenced by the Balmer lines. The profile shape…

Astrophysics · Physics 2009-10-22 Paolo Marziani , Jack W. Sulentic

By observing the near-infrared spectrum of the quasar PG 1116+215 at z = 0.176 and combining with the HST/FOS spectrum, we obtained the relative strengths of three permitted OI lines ({lambda}1304, {lambda}8446, and {lambda}11287) in a…

Astrophysics · Physics 2015-06-24 Yoshiki Matsuoka , Shinki Oyabu , Yumihiko Tsuzuki , Kimiaki Kawara , Yuzuru Yoshii

We report the results of 3D spectroscopic observations of Mrk 493 (NLS1 galaxy) with the integral-field spectrograph MPFS of the SAO RAS 6-m telescope. The difference in the slope of the optical continuum emission intensity across the…

Astrophysics · Physics 2009-11-13 L. C. Popovic , A. A. Smirnova , J. Kovacevic , A. V Moiseev , V. L. Afanasiev
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