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Related papers: A Complete Sample of Soft X-ray Selected AGN: I. T…

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We have examined ROSAT soft X-ray observations of a complete, distance-limited sample of Seyfert and LINER galaxies. X-ray data are available for 46 out of 60 such objects which lie within a hemisphere of radius 18 Mpc. We have constructed…

Astrophysics · Physics 2009-11-06 Eve L. Halderson , Edward C. Moran , Alexei V. Filippenko , Luis C. Ho

We present a sample of 8 nearby Seyfert 2 galaxies observed by HST and Chandra. All of the sources present soft X-ray emission which is coincident in extension and overall morphology with the [OIII] emission. The spectral analysis reveals…

Astrophysics · Physics 2009-11-11 Stefano Bianchi , Matteo Guainazzi , Marco Chiaberge

We report a detailed analysis of the XMM-Newton spectra of six Narrow-Line Seyfert 1 (NLS1) galaxies at redshift z = 0.35--0.92. Compared with the NLS1s at lower redshift in the previously most-studied sample, these NLS1s have larger black…

High Energy Astrophysical Phenomena · Physics 2023-05-25 Zhibo Yu , Jiachen Jiang , Cosimo Bambi , Luigi C. Gallo , Dirk Grupe , Andrew C. Fabian , Christopher S. Reynolds , William N. Brandt

The Seyfert 1 galaxy, Ark 120, is a prototype example of the so-called class of bare nucleus AGN, whereby there is no known evidence for the presence of ionized gas along the direct line of sight. Here deep ($>400$ ks exposure), high…

High Energy Astrophysical Phenomena · Physics 2016-09-21 James Reeves , Delphine Porquet , Valentina Braito , Emanuele Nardini , Andrew Lobban , Jane Turner

In this paper we study the properties of the optical spectra of Type 1 active galactic nuclei (AGNs) by using the unobscured hard X-ray emission as a diagnostic. We develop the `Correlation Spectrum Technique' (CST) and use this to show the…

High Energy Astrophysical Phenomena · Physics 2015-06-04 C. Jin , M. Ward , C. Done

Recently growing evidence has been accumulated that the NLS1s are viewed from nearly pole-on viewing angles. However, there has been no theoretical model which explains the following important correlations; 1) weaker optical Fe II emitters…

Astrophysics · Physics 2007-05-23 Yoshiaki Taniguchi , Takashi Murayama , Tohru Nagao

We report X-ray fluxes in the 2--10 keV band from LINERs (low-ionization nuclear emission-line regions) and low-luminosity Seyfert galaxies obtained with the ASCA satellite. Observed X-ray luminosities are in the range between 4e39 and 5e41…

Astrophysics · Physics 2009-10-31 Yuichi Terashima , Luis C. Ho , Andrew F. Ptak

Based on photoionization calculations we present a study of the NLR emission line ratios of Narrow-line Seyfert 1 (NLS1) galaxies. In particular, we investigate the influence of different EUV - soft-X-ray spectral shapes (a giant soft…

Astrophysics · Physics 2007-05-23 S. Komossa , D. Grupe , M. Janek

We report the discovery and analysis of the follow-up ROSAT pointed observation, an ASCA observation and optical and radio observations of the enigmatic soft X-ray AGN RX J0134.2-4258. In the optical, RX J0134.2-4258 appears as an extreme…

Astrophysics · Physics 2007-05-23 D. Grupe , K. M. Leighly , H. -C. Thomas , S. A. Laurent-Muehleisen

The Swift Burst Alert Telescope (BAT) survey of Active Galactic Nuclei (AGN) is providing an unprecedented view of local AGNs (<z> = 0.03) and their host galaxy properties. In this paper, we present an analysis of the optical spectra of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Lisa M. Winter , Karen T. Lewis , Michael Koss , Sylvain Veilleux , Brian Keeney , Richard F. Mushotzky

In this contribution we report on the study of the optical emission lines and X-ray spectra of a sample of Type 1 AGNs, collected at the Sloan Digital Sky Survey database and observed by the XMM Newton satellite. Exploiting the different…

High Energy Astrophysical Phenomena · Physics 2018-03-14 G. La Mura , S. Ciroi , V. Cracco , D. Ilić , L. Č. Popović , P. Rafanelli

We have surveyed 188 ROSAT PSPC fields for X-ray sources with hard spectra (alpha<0.5); such sources must be major contributors to the X-ray background at faint fluxes. In this paper we present optical identifications for 62 of these…

Astrophysics · Physics 2009-11-06 M. J. Page , J. P. D. Mittaz , F. J. Carrera

We present the broad-band soft and hard X-ray spectral analysis of 8 Narrow Line Seyfert 1 galaxies extracted from the IBISCO Sample. The study also focuses on the properties of the NLS1 in our sample in relation to those of the IBISCO…

High Energy Astrophysical Phenomena · Physics 2018-07-17 Manuela Molina , Angela Malizia , Fabrizio Fiore , Chiara Feruglio

We have investigated the X-ray spectral properties of a sample of 138 X-ray sources detected serendipitously in $XMM-Newton$ observations of the Galactic plane, at an intermediate to faint flux level. We divide our sample into 5 subgroups…

High Energy Astrophysical Phenomena · Physics 2015-06-18 R. S. Warwick , K. Byckling , D. Pérez-Ramírez

This paper presents a quantification of the X-ray variability amplitude for 79 ASCA observations of 36 Seyfert 1 galaxies. We find that consideration of sources with the narrowest permitted lines in the optical band introduces scatter into…

Astrophysics · Physics 2009-10-31 T. J. Turner , I. M. George , K. Nandra , D. Turcan

We analyze the $2-10$~keV X-ray emission of complete samples of AGN and galaxies selected at 12$\mu$m and recently compiled by Rush, Malkan \& Spinoglio (1993). As a necessary complement we also study the IR emissivity of the largest sample…

Astrophysics · Physics 2016-08-30 X. Barcons , A. Franceschini , G. De Zotti , L. Danese , T. Miyaji

We present modeling and interpretation of the continuum and emission lines for a sample of 51 unobscured Type 1 active galactic nuclei (AGN). All of these AGNs have high quality spectra from both XMM-Newton and Sloan Digital Sky Survey…

High Energy Astrophysical Phenomena · Physics 2015-05-30 C. Jin , M. Ward , C. Done , J. M. Gelbord

Seyfert-type AGN that exhibit unusually strong and steep soft X-ray spectra are reviewed, building on observations made during the ROSAT all-sky survey. Two individual cases are described in brief detail, both being identified initially in…

Astrophysics · Physics 2007-05-23 K. A. Pounds , W. N. Brandt

We analyse the spectra of the archival XMM-Newton data of the Seyfert 1 AGN Zw 229.015 in the energy range $0.3 - 10.0$ keV. When fitted with a simple power-law, the spectrum shows signatures of weak soft excess below 1.0 keV. We find that…

Astrophysics of Galaxies · Physics 2016-12-21 Oluwashina Adegoke , Suvendu Rakshit , Banibrata Mukhopadhyay

(I) We observed eight Seyfert~2s and two X--ray--weak Seyfert~1/QSOs with the ROSAT PSPC, and one Seyfert~2 with the ROSAT HRI. These targets were selected from the Extended 12\um\ Galaxy Sample. (II) Both Seyfert~1/QSOs vary by factors of…

Astrophysics · Physics 2009-10-28 Brian Rush , Matthew A. Malkan