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Related papers: Giant radio quasars: composite optical spectra

200 papers

Using the Spitzer Space Telescope, we have obtained rest frame 9-16mu spectra of 11 quasars and 9 radio galaxies from the 3CRR catalog at redshifts 1.0<z<1.4. This complete flux-limited 178MHz-selected sample is unbiased with respect to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 C. Leipski , M. Haas , S. P. Willner , M. L. N. Ashby , B. J. Wilkes , G. G. Fazio , R. Antonucci , P. Barthel , R. Chini , P. Ogle , R. Siebenmorgen , F. Heymann

(Abridged) We construct a catalog of radio sources detected by the GB6 (6 cm), FIRST and NVSS (20 cm), and WENSS (92 cm) radio surveys, and the SDSS optical survey. The 2.7 million entries in the publicly-available master catalog are…

Astrophysics · Physics 2009-01-16 Amy E. Kimball , Željko Ivezić

We present the first results from the Quasar Feedback Survey, a sample of 42 z<0.2, [O III] luminous AGN (L[O III]>10^42.1 ergs/s) with moderate radio luminosities (i.e. L(1.4GHz)>10^23.4 W/Hz; median L(1.4GHz)=5.9x10^23 W/Hz). Using high…

We report spectral, imaging, and variability results from four new XMM-Newton observations and two new Chandra observations of high-redshift (z > 4) radio-loud quasars (RLQs). Our targets span lower, and more representative, values of radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 C. Saez , W. N. Brandt , O. Shemmer , L. Chomiuk , L. A. Lopez , H. L. Marshall , B. P. Miller , C. Vignali

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

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 study the morphology of the radio emission of giant radio galaxies (GRGs), a rare type of active galaxies, in order to find new clues for the reasons of their large size. Using radio images from two sky surveys at 1.4 GHz we quantified…

Astrophysics of Galaxies · Physics 2016-10-11 Elizabeth López Vázquez , Heinz Andernach

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

We have recently used the Faint Images of the Radio Sky at Twenty-centimeters (FIRST) survey to show that red quasars have fundamentally different radio properties to typical blue quasars: a significant (factor $\sim3$) enhancement in the…

Astrophysics of Galaxies · Physics 2020-04-10 V. A. Fawcett , D. M. Alexander , D. J. Rosario , L. Klindt , S. Fotopoulou , E. Lusso , L. K. Morabito , G. Calistro Rivera

We present spectroscopic measurements for 226 sources from the Gemini Near Infrared Spectrograph - Distant Quasar Survey (GNIRS-DQS). Being the largest uniform, homogeneous survey of its kind, it represents a flux-limited sample ($m_{i}$…

A key argument in favor of orientation based unification schemes is the finding that among the most powerful 3CRR radio sources the (apparent) median linear size of quasars is smaller than that of radio galaxies, which supports the idea…

Astrophysics · Physics 2009-10-28 Gopal-Krishna , Vasant Kulkarni , Paul J. Wiita

Red quasars exhibit a higher incidence of compact (galaxy-scale or smaller) radio emission than blue quasars, arising from systems near the radio-loud/radio-quiet threshold. In this paper we select quasars from SDSS ($0.2 <z <2.4$), and use…

We have constructed a sample of radio-loud and radio-quiet quasars from the Faint Im- ages Radio Sky at Twenty-one centimetres (FIRST) and the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), over the H-ATLAS Phase 1 Area (9h, 12h and…

We present spectroscopic observations of a sample of faint Gigahertz Peaked Spectrum (GPS) radio sources drawn from the Westerbork Northern Sky Survey (WENSS). Redshifts have been determined for 19 (40%) of the objects. The optical spectra…

We present the results of an investigation into the X-ray properties of radio-intermediate and radio-loud quasars (RIQs and RLQs, respectively). We combine large, modern optical (e.g., SDSS) and radio (e.g., FIRST) surveys with archival…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 B. P. Miller , W. N. Brandt , D. P. Schneider , R. R. Gibson , A. T. Steffen , Jianfeng Wu

We present the results of Chandra ACIS-S snapshot observations of six radio-loud quasars (RLQs) at z=3.5-4.7. These observations sample luminous RLQs with moderate-to-high radio-loudness (R=200-9600) and aim to connect the X-ray properties…

Astrophysics · Physics 2008-11-26 L. A. Lopez , W. N. Brandt , C. Vignali , D. P. Schneider , G. Chartas , G. P. Garmire

We present the result of 27 ASCA observations of 26 radio-quiet quasars (RQQs) from the PG survey. All the RQQs were detected except 2 BALQSOs. We find the variability characteristics of the sources to be consistent with Seyf-1s. A powerlaw…

Astrophysics · Physics 2009-10-31 I. M. George , T. J. Turner , T. Yaqoob , H. Netzer , A. Laor , R. F. Mushotzky , K. Nandra , T. Takahashi

Quasars are objects of high interest in extragalactic astrophysics, cosmology, and astrometry. One of their useful qualities is their potential radio loudness. However, the fraction of radio-loud vs. radio-quiet quasars is subject to…

Astrophysics of Galaxies · Physics 2025-08-26 Nestor Arsenov , Sandor Frey , András Kovács , Lyuba Slavcheva-Mihova

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 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…