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Related papers: The EMSS Radio Loud Quasar Sample

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We construct the first X-ray selected sample of broad line radio-loud AGN from the EMSS survey. In order to test unifying schemes for radio-loud objects, their spectral and statistical properties (both flat and steep spectrum objects) are…

Astrophysics · Physics 2009-11-06 Anna Wolter , Annalisa Celotti

We analyze the optical properties of Radio-Loud quasars along the Main Sequence (MS) of quasars. A sample of 355 quasars selected on the basis of radio detection was obtained by cross-matching the FIRST survey at 20cm and the SDSS DR12…

Astrophysics of Galaxies · Physics 2021-07-14 A. del Olmo , P. Marziani , V. Ganci , M. D'Onofrio , E. Bon , N. Bon , A. C. Negrete

We have used the VLA FIRST survey and the APM catalog of the POSS-I plates as the basis for constructing a new radio-selected sample of optically bright quasars. This is the first radio-selected sample that is competitive in size with…

This paper presents the first high-resolution and high-sensitivity study of the radio properties of optically selected type~2 quasars. We used the Very Large Array at 8.4 GHz to observe 59 sources drawn from the Sloan Digital Sky Survey…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Dharam Vir Lal , Luis C. Ho

A sample of 103 quasars from the Large Bright Quasar Survey (LBQS) has been observed with the VLA at 8.4 GHz to study the evolution of the radio luminosity distribution and its dependence on absolute magnitude. Radio data from pointed…

Astrophysics · Physics 2008-11-26 Eric J. Hooper , Chris D. Impey , Craig B. Foltz , Paul C. Hewett

A database of radio-quiet quasars detected with ROSAT is presented containing 846 quasars seen in the All-Sky Survey and/or in pointed PSPC observations. About 70% of the objects have been detected in X-rays for the first time. We present…

Astrophysics · Physics 2008-11-26 W. Yuan , W. Brinkmann , J. Siebert , W. Voges

(Abridged) We report on the X-ray and multiwavelength properties of 11 radio-quiet quasars with weak or no emission lines identified by the Sloan Digital Sky Survey (SDSS) with redshift z=0.4-2.5. The distribution of relative X-ray…

We present simultaneous optical and X-ray data from Swift for a sample of FSRQs selected from the EMSS survey. We present also a complete analysis of Swift and INTEGRAL data on 4 blazars recently discussed as possibly challenging the trends…

Astrophysics · Physics 2009-11-13 L. Maraschi , L. Foschini , G. Ghisellini , F. Tavecchio , R. M. Sambruna

We describe the selection of candidate radio-loud quasars obtained by cross-matching radio source positions from the low-frequency (151 MHz) 7C survey with optical positions from five pairs of EO POSS-I plates scanned with the Cambridge…

We present simultaneous multifrequency radio observations for a complete subsample of 26 XBLs from the Einstein Extended Medium-Sensitivity Survey, obtained with the Very Large Array (VLA). Spectra are computed using fluxes at 20, 6 and 3.6…

Astrophysics · Physics 2009-11-10 Francesca Cavallotti , Anna Wolter , John T. Stocke , Travis Rector

We present the final results of a ROSAT PSPC program to study the soft X-ray emission properties of a complete sample of low $z$ quasars. The main results are: 1. There is no evidence for significant soft excess emission or excess…

Astrophysics · Physics 2009-10-28 Ari Laor , Fabrizio Fiore , Martin Elvis , Belinda J. Wilkes , Jonathan C. McDowell

We present the soft X-ray (0.1--2.4 keV) properties of a complete sample of 88 southern radio sources derived from the Wall \& Peacock 2-Jy sample. It comprises 68 radio galaxies, 18 quasars and 2 BL Lac objects. Whereas both BL Lac objects…

We present the first deep VLA radio images of flat-spectrum radio quasars (FSRQ) with multiwavelength emission properties similar to those of BL Lacs with synchrotron X-rays. Our observations of twenty-five of these sources show that their…

Astrophysics · Physics 2009-11-13 Hermine Landt , Eric S. Perlman , Paolo Padovani

We use statistical results from a large sample of about 500 blazars, based on two surveys, the Deep X-ray Radio Blazar Survey (DXRBS), nearly complete, and the RASS-Green Bank survey (RGB), to provide new constraints on the spectral energy…

Astrophysics · Physics 2009-11-07 P. Padovani , E. Perlman , H. Landt , P. Giommi , M. Perri

ROSAT observations of a large sample of bright gamma-ray (E > 100 MeV) blazars are presented. Results of a detailed spectral analysis in the soft $\sim$ 0.1-2.0 keV energy range are discussed in relation to the overall energy distribution…

Astrophysics · Physics 2016-08-30 A. Comastri , G. Fossati , G. Ghisellini , S. Molendi

It is been known for more than a decade that BALQSOs (broad absorption line quasars) are highly attenuated in the X-ray regime compared to other quasars, especially in the soft band ($< $ 1 keV). Using X-ray selection techniques we have…

Astrophysics · Physics 2009-11-13 Kajal K. Ghosh , Brian Punsly

We identified a large sample of radio quasars, including those with complex radio morphology, from the Sloan Digital Sky Survey (SDSS) and the Faint Images of Radio Sky at Twenty-cm (FIRST). Using this sample, we inspect previous radio…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-21 Yu Lu , Tinggui Wang , Hongyan Zhou , Jian Wu

Optically luminous quasars at $z > 5$ are important probes of super-massive black hole (SMBH) formation. With new and future radio facilities, the discovery of the brightest low-frequency radio sources in this epoch would be an important…

We have obtained single-epoch optical photometry for 201 quasars, taken from the FIRST Bright Quasar Survey, which span a wide range in radio loudness. Comparison with the magnitudes of these objects on the POSS-I plates provides by far the…

We measure the spectral properties of a representative sub-sample of 187 quasars, drawn from the Parkes Half-Jansky, Flat-radio-spectrum Sample (PHFS). Quasars with a wide range of rest-frame optical/UV continuum slopes are included in the…

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