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Related papers: What does Civ{\lambda}1549 tell us about the physi…

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Using 190,000 spectra from the seventeenth data release of the Sloan Digital Sky Survey, we investigate the ultraviolet emission line properties in z=2 quasars. Specifically, we quantify how the shape of CIV 1549A and the equivalent width…

We aim to evaluate the behaviour of our 22 high-redshift (2.2 < z < 3.7) and high-luminosity (47.39 < Lbol < 48.36) quasars in the context of the 4-Dimensional Eigenvector 1. Our approach involves studying quasar physics through…

Astrophysics of Galaxies · Physics 2023-01-18 A. Deconto-Machado , A. del Olmo , P. Marziani , J. Perea , G. M. Stirpe

We study the geometry of the Hbeta broad emission region by comparing the M_BH values derived from Hbeta through the virial relation with those obtained from the host galaxy luminosity in a sample of 36 low redshift (z around 0.3) quasars.…

Astrophysics · Physics 2009-11-13 R. Decarli , M. Labita , A. Treves , R. Falomo

We investigate the relationship between the rest-frame equivalent width (EW) of the C IV \lambda1549 broad-emission line, monochromatic luminosity at rest-frame 5100 A, and the Hbeta-based Eddington ratio in a sample of 99 ordinary quasars…

Astrophysics of Galaxies · Physics 2015-06-03 Ohad Shemmer , Sara Lieber

The ultraviolet (UV) spectra of 16 blazars (<z> ~1) from the archives of the Hubble Space Telescope Faint Object Spectrograph have been analyzed in order to study in a systematic way the properties oftheir broad UV emission lines. We find…

Astrophysics · Physics 2009-11-13 Elena Pian , Renato Falomo , Aldo Treves

Using a sample of 30,000 quasars from SDSS-DR7, we explore the range of properties exhibited by high-ionization, broad emission lines, such as CIV 1549. Specifically we investigate the anti-correlation between L_UV and emission line EQW…

We review the basic techniques for extracting information about quasar structure and kinematics from the broad emission lines in quasars. We consider which lines can most effectively serve as virial estimators of black hole mass. At low…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Jack W. Sulentic , Paola Marziani , Ascension del Olmo , Ilse Plauchu-Frayn

The X-shooter instrument on the VLT was used to obtain spectra of seven moderate-redshift quasars simultaneously covering the spectral range 3000 Ang to 2.5 microns. At z ~ 1.5, most of the prominent broad emission lines in the ultraviolet…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Luis C. Ho , Paolo Goldoni , Xiao-Bo Dong , Jenny E. Greene , Gabriele Ponti

[Abridged] We present new VLT ISAAC spectra for 30 quasars, which we combine with previous data to yield a sample of 53 intermediate redshift (z ~ 0.9 - 3.0) sources. The sample is used to explore properties of prominent lines in the Hbeta…

Astrophysics · Physics 2009-11-13 P. Marziani , J. W. Sulentic , G. M. Stirpe , S. Zamfir , M. Calvani

We present evidence that the high-velocity CIV lambda 1549 emission line gas of radio-loud quasars may originate in a disk-like configuration, in close proximity to the accretion disk often assumed to emit the low-ionization lines. For a…

Astrophysics · Physics 2009-10-31 M. Vestergaard , B. J. Wilkes , P. D. Barthel

Outflows from super-massive black holes (SMBHs) play an important role in the co-evolution of themselves, their host galaxies, and the larger scale environments. Such outflows are often characterized by emission and absorption lines in…

We present high S/N UV spectra for eight quasars at z $\sim$ 3 obtained with VLT/FORS. The spectra enable us to analyze in detail the strong and weak emission features in the rest-frame range 1300-2000 A of each source (Ciii]$\lambda$1909,…

Astrophysics of Galaxies · Physics 2015-06-19 C. A. Negrete , D. Dultzin , P. Marziani , J. W. Sulentic

We present the single-epoch black hole mass estimators based on the CIV (1549 A) broad emission line, using the updated sample of the reverberation-mapped AGNs and high-quality UV spectra. By performing multi-component spectral fitting…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Daeseong Park , Jong-Hak Woo , Kelly Denney , Jaejin Shin

We studied the spectra of six $z \sim 2.2$ quasars obtained with the X-shooter spectrograph at the Very Large Telescope. The redshift of these sources and X-shooter's spectral coverage allow us to cover the rest spectral range $\sim1200 -…

Single-epoch virial black hole (BH) mass estimators utilizing broad emission lines have been routinely applied to high-redshift quasars to estimate their BH masses. Depending on the redshift, different line estimators (Halpha, Hbeta, MgII,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Yue Shen , Xin Liu

Accretion processes in quasars and active galactic nuclei are still poorly understood, especially as far as the connection between observed spectral properties and physical parameters is concerned. Quasars show an additional degree of…

Astrophysics · Physics 2007-05-23 Paola Marziani , Deborah Dultzin-Hacyan , Jack W. Sulentic

With a quasar sample designed for studying orientation effects, we investigate the orientation dependence of characteristics of the C IV 1549 broad emission line in approximately 50 Type 1 quasars with z=0.1-1.4. Orientation is measured for…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Jessie C. Runnoe , M. S. Brotherton , M. A. DiPompeo , Zhaohu Shang

The 4D Eigenvector 1 parameter space was introduced seven years ago as an attempt at multiwavelength spectroscopic representation of quasars. It appears to be the most effective diagnostic space for unifying the diversity of broad line AGN.…

Astrophysics · Physics 2007-09-18 Jack W. Sulentic , Sebastian Zamfir , Paola Marziani , Deborah Dultzin

We present Adaptive Optics assisted near-IR integral field spectroscopic observations of a luminous quasar at $z = 2.4$, previously observed as the first known example at high redshift of large scale quasar-driven outflow quenching star…

Astrophysics of Galaxies · Physics 2017-03-22 R. J. Williams , R. Maiolino , Y. Krongold , S. Carniani , G. Cresci , F. Mannucci , A. Marconi