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Related papers: Fe K Line Profile in Low-redshift Quasars: Average…

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The properties of the fluorescence Fe K-alpha emission lines of a sample of 38 quasars (QSOs) observed with XMM-Newton are studied. These objects are included in the optically selected sample from the Palomar-Green (PG) Bright Quasar Survey…

In this paper, the dependence of the broad Fe K$\alpha$ line on the physical parameters of AGN, such as the black hole mass $M_{BH}$, accretion rate (equivalently represented by Eddington ratio $\lambda_{Edd}$), and optical classification,…

High Energy Astrophysical Phenomena · Physics 2016-10-03 Zhu Liu , Weimin Yuan , Youjun Lu , Francisco J. Carrera , Serena Falocco , Xiao-Bo Dong

Super-Eddington accretion is a crucial phase in the growth of supermassive black holes. However, identifying super-Eddington accreting quasars observationally is challenging due to uncertain black-hole mass estimates and other…

High Energy Astrophysical Phenomena · Physics 2025-10-29 Ying Chen , Bin Luo , Jian Huang

We report results from an XMM-Newton observation of the broad-line radio galaxy 3C109 (z=0.3056). Confirming previous results, an Fe emission line is detected, possibly comprising a broad component. However, the data cannot distinguish…

Astrophysics · Physics 2009-09-17 G. Miniutti , D. R. Ballantyne , S. W. Allen , A. C. Fabian , R. R. Ross

We report a Chandra high-energy grating detection of a narrow, redshifted absorption line superimposed on the red wing of a broad Fe K line in the $z=0.297$ quasar E1821+643. The absorption line is detected at a confidence level, estimated…

Astrophysics · Physics 2009-11-10 T. Yaqoob , P. J. Serlemitsos

We present an X-ray spectral analysis of 21 low redshift quasars observed with XMM-Newton EPIC. All the sources are Palomar Green quasars with redshifts between 0.05 and 0.4 and have low Galactic absorption along the line-of-sight. A large…

Astrophysics · Physics 2016-08-30 D. Porquet , J. N. Reeves , P. O'Brien , W. Brinkmann

We present bolometric luminosities, black hole masses and Eddington ratios for 42 luminous quasars at z>6 using high signal-to-noise ratio VLT/X-Shooter spectra, acquired in the enlarged ESO Large Programme XQR-30. In particular, we derive…

We present an {\it XMM-Newton} EPIC observation of HE0450-2958 which may be a ``naked''quasar as suggested by Magain et al. The \xmm EPIC spectra show a substantial soft X-ray excess, a steep photon index, as well as marginal evidence for a…

Astrophysics · Physics 2008-11-26 Xin-Lin Zhou , Fang Yang , Xiao-Rong Lv , Jian-Min Wang

We present the results of the uniform analysis of 46 XMM-Newton observations of six BAL and seven mini-BAL QSOs belonging to the Palomar-Green Quasar catalogue. Moderate-quality X-ray spectroscopy was performed with the EPIC-pn, and allowed…

High Energy Astrophysical Phenomena · Physics 2016-05-25 Margherita Giustini

It has been recently discovered that a few super-Eddington sources undergoing black hole super-Eddington accretion exhibit X-ray reflection signatures. In such new systems, one expects that the coronal X-ray emissions are mainly reflected…

The Fe-K line, an important physical diagnostic in the X-ray spectra of AGN, has been notoriously difficult to measure in the high-luminosity, radio-loud quasar 3C 273 (z=0.158). On the few occasions that it has been detected its intrinsic…

Astrophysics · Physics 2009-10-31 T. Yaqoob , P. J. Serlemitsos

We address the effect of orientation of the accretion disk plane and the geometry of the broad-line region (BLR) as part of an effort to understand the distribution of quasars in the optical plane of the quasar main sequence. We utilize the…

High Energy Astrophysical Phenomena · Physics 2019-09-11 Swayamtrupta Panda , Paola Marziani , Bożena Czerny

Quasars accretion models predict a broad range of optical and ultraviolet properties that depend primarily on black hole mass and accretion rate. Yet, most optically selected luminous quasars display strikingly similar continuum spectra. We…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-28 G. Risaliti , B. Trefoloni , M. Salvati

X-ray reflection spectra from photoionized accretion discs in active galaxies are presented for a wide range of illumination conditions. The energy, equivalent width (EW) and flux of the Fe K line are shown to depend strongly on the ratio…

Astrophysics · Physics 2009-11-07 D. R. Ballantyne , R. R. Ross

We perform a spectral analysis of a sample of 11 medium redshift (1.5 < z < 2.2) quasars. Our sample all have optical spectra from the SDSS, infrared spectra from GNIRS and TSPEC, and X-ray spectra from XMM-Newton. We first analyse the…

High Energy Astrophysical Phenomena · Physics 2015-06-23 James S. Collinson , Martin J. Ward , Chris Done , Hermine Landt , Martin Elvis , Jonathan C. McDowell

The Eddington ratio is a key parameter that governs the diversity of quasar properties. It can be scaled with a strong anti-correlation between optical Fe II and [O III] emission. In search of such indicators in the far-UV band, the HST…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 Wei Zheng

We report the discovery of narrow X-ray absorption features from the dipping low-mass X-ray binary X 1624-490 during an XMM-Newton observation in 2001 February. The features are identified with the K alpha absorption lines of Fe xxv and Fe…

Astrophysics · Physics 2009-11-07 A. N. Parmar , T. Oosterbroek , L. Boirin , D. Lumb

Broad Fe K-alpha emission lines have recently been reported in a number of Galactic black holes. Such lines are useful accretion flow diagnostics because they may be produced at the inner accretion disk and shaped by relativistic effects,…

We present a detailed analysis of the XMM-Newton long-look of the Seyfert galaxy IC 4329a. The Fe K bandpass is dominated by two resolved peaks at 6.4 keV and 7.0 keV, consistent with neutral or near-neutral Fe K alpha and K beta emission.…

Astrophysics · Physics 2008-11-26 A. Markowitz , J. Reeves , V. Braito

We present XMM-Newton/EPIC spectra for the Laor et al. sample of Palomar Green quasars. We find that a power-law provides a reasonable fit to the 2-5 keV region of the spectra. Excess soft X-ray emission below 2 keV is present for all…

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