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Related papers: The 2dF BL Lac Survey II

200 papers

Aims: We present optical spectroscopy of a sample of BL Lac objects, to determine their redshift, to study their broad emission line properties and to characterize their close environment. Methods: Twelve objects were observed using the ESO…

Astrophysics · Physics 2009-11-11 B. Sbarufatti , R. Falomo , A. Treves , J. Kotilainen , .

We present optical identifications and radio spectra for ten radio sources from two flux-density-complete samples. Radio variability characteristics are presented for four objects. The observations were obtained on the RATAN-600 radio…

Astrophysics · Physics 2009-11-07 V. Chavushyan , R. Mujica , A. G. Gorshkov , V. K. Konnikova , M. G. Mingaliev , J. R. Valdez

We present radio observations of 19 candidate compact steep-spectrum (CSS) objects selected from a well-defined, complete sample of 52 B2 radio sources of intermediate strength. These observations were made with the VLA A-array at 4.835…

Astrophysics · Physics 2009-11-07 D. J. Saikia , P. Thomasson , R. E. Spencer , F. Mantovani , C. J. Salter , S. Jeyakumar

The main goal of the FIRST-APM QSO Survey (FAQS) survey is to compile the most complete sample of Bright QSOs, located in the well optically investigated area of the sky covered by the Second Byurakan Survey (SBS). We do that through the…

Astrophysics · Physics 2007-05-23 V. H. Chavushyan , V. O. Verkhodanov , R. Mujica , L. Carrasco

AIMS. We are studying an unbiased sample of 42 nearby (z < 0.2) BL Lacertae objects with a multi-wavelength approach. The results of VLBI observations were presented in the first paper of this series. In this paper, we study the…

High Energy Astrophysical Phenomena · Physics 2018-11-08 F. D'Ammando , M. Giroletti , S. Rainò

This paper describes spectra of quasar candidates acquired during the commissioning phase of the Low-Resolution Spectrograph of the Hobby-Eberly Telescope. The objects were identified as possible quasars from multicolor image data from the…

Astrophysics · Physics 2008-11-26 D. P. Schneider , Gary J. Hill , X. Fan , L. W. Ramsey

As a follow-up of the optical spectroscopic campaign aimed at achieving completeness in the Third Catalog of Hard Fermi-LAT Sources (3FHL), we present here the results of a sample of 28 blazars of uncertain type observed using the 4m…

High Energy Astrophysical Phenomena · Physics 2021-06-02 M. Rajagopal , S. Marchesi , A. Kaur , A. Domínguez , R. Silver , M. Ajello

The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing sensitive, high-resolution 120-168MHz survey of the entire northern sky for which observations are now 20% complete. We present our first full-quality public data release. For this data…

Astrophysics of Galaxies · Physics 2018-11-21 T. W. Shimwell , C. Tasse , M. J. Hardcastle , A. P. Mechev , W. L. Williams , P. N. Best , H. J. A. Röttgering , J. R. Callingham , T. J. Dijkema , F. de Gasperin , D. N. Hoang , B. Hugo , M. Mirmont , J. B. R. Oonk , I. Prandoni , D. Rafferty , J. Sabater , O. Smirnov , R. J. van Weeren , G. J. White , M. Atemkeng , L. Bester , E. Bonnassieux , M. Brüggen , G. Brunetti , K. T. Chyży , R. Cochrane , J. E. Conway , J. H. Croston , A. Danezi , K. Duncan , M. Haverkorn , G. H. Heald , M. Iacobelli , H. T. Intema , N. Jackson , M. Jamrozy , M. J. Jarvis , R. Lakhoo , M. Mevius , G. K. Miley , L. Morabito , R. Morganti , D. Nisbet , E. Orrú , S. Perkins , R. F. Pizzo , C. Schrijvers , D. J. B. Smith , R. Vermeulen , M. W. Wise , L. Alegre , D. J. Bacon , I. M. van Bemmel , R. J. Beswick , A. Bonafede , A. Botteon , S. Bourke , M. Brienza , G. Calistro Rivera , R. Cassano , A. O. Clarke , C. J. Conselice , R. J. Dettmar , A. Drabent , C. Dumba , K. L. Emig , T. A. Enßlin , C. Ferrari , M. A. Garrett , R. T. Génova-Santos , A. Goyal , G. Gürkan , C. Hale , J. J. Harwood , V. Heesen , M. Hoeft , C. Horellou , C. Jackson , G. Kokotanekov , R. Kondapally , M. Kunert-Bajraszewska , V. Mahatma , E. K. Mahony , S. Mandal , J. P. McKean , A. Merloni , B. Mingo , A. Miskolczi , S. Mooney , B. Nikiel-Wroczyński , S. P. O'Sullivan , J. Quinn , W. Reich , C. Roskowiński , A. Rowlinson , F. Savini , A. Saxena , D. J. Schwarz , A. Shulevski , S. S. Sridhar , H. R. Stacey , S. Urquhart , M. H. D. van der Wiel , E. Varenius , B. Webster , A. Wilber

We present the scientific goals, the strategy and the first results of the REX project, an effort aimed at creating a sizable and statistically complete sample of Radio Emitting X-ray sources (REX) using the available data from a VLA survey…

Astrophysics · Physics 2009-10-31 A. Caccianiga , T. Maccacaro , A. Wolter , R. Della Ceca , I. M. Gioia

The multi-frequency Sedentary Survey is a flux limited, statistically well-defined sample of highly X-ray dominated BL Lacertae objects (HBLs) which includes 150 sources. In this paper, the third of the series, we report the results of a…

Astrophysics · Physics 2009-11-13 S. Piranomonte , M. Perri , P. Giommi , H. Landt , P. Padovani

While BL Lacertae objects are widely believed to be highly beamed, low-luminosity radio galaxies, many radio-selected BL Lacs have extended radio power levels and optical emission lines that are too luminous to be low-luminosity radio…

Astrophysics · Physics 2009-11-07 T. A. Rector , J. T. Stocke

We use redshift determinations and spectral analysis of galaxies in the 2dF Galaxy Redshift Survey to study the properties of local radio sources with $S\ge 1$ mJy. 557 objects drawn from the FIRST survey, corresponding to 2.3 per cent of…

We report preliminary results of a visual inspection of ~4300 deg$^2$ covered by 4414 images of the 3-GHz VLA Sky Survey (VLASS, epoch 1.1) in search of extended radio structures. Over 7600 positions were registered, and for a subset of 270…

Astrophysics of Galaxies · Physics 2018-08-23 Agueda C. Villarreal Hernández , Heinz Andernach

The Third Catalog of Hard Fermi Large Area Telescope Sources (3FHL) reports the detection of 1556 objects at E > 10 GeV. However, 177 sources remain unassociated and 23 are associated with a ROSAT X-ray detection of unknown origin. Pointed…

High Energy Astrophysical Phenomena · Physics 2022-12-07 S. Joffre , R. Silver , M. Rajagopal , M. Ajello , N. Torres-Albà , A. Pizzetti , S. Marchesi , A. Kaur

Among active galactic nuclei, BL Lac objects show extreme properties that have been interpreted as the effect of relativistic beaming on the emission from a plasma jet oriented close to the line of sight. The Doppler amplification of the…

Astrophysics of Galaxies · Physics 2015-06-29 Alessandro Capetti , Claudia M. Raiteri

This paper presents a new sample of BL Lac objects selected from a deep (30 mJy) radio survey of flat spectrum radio sources (the CLASS blazar survey, henceforth CBS). The sample is one of the largest well defined samples in the low power…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. J. M. Marcha , A. Caccianiga

Continuing our program of spectroscopic observations of ICRF sources, we present redshifts for 120 quasars and radio galaxies. Data were obtained with five telescopes: the 3.58m ESO New Technology Telescope (NTT), the two 8.2m Gemini…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-15 Oleg Titov , Laura M. Stanford , Helen M. Johnston , Tapio Pursimo , Richard W. Hunstead , David L. Jauncey , K. Maslennikov , A. Boldycheva

We investigate the properties of the three BL Lac objects, PKS 2201+044, 3C 371 and PKS 0521-365, that exhibit prominent optical jets. We present high resolution near-IR images of the jet of the first two, obtained with an innovative…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 E. Liuzzo , R. Falomo , A. Treves

We present the results from a survey of i-dropout objects selected from ~1550 deg^2 of multicolor imaging data from the Sloan Digital Sky Survey, to search for luminous quasars at z>5.8. Objects with i*-z*>2.2 and z*<20.2 are selected, and…