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Related papers: A Large Sample of BL Lacs from SDSS and FIRST

200 papers

Combining newly identified and previously known BL Lacs from the RASS-Green Bank (RGB) catalog, we present a sample of 127 BL Lacs, the largest ever derived from a single uniform survey. A Complete sample of 33 objects brighter than O=18.0…

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

We present new optical and near-IR spectroscopy as well as new high dynamic range, arcsecond-resolution VLA radio maps of BL Lacs from the complete radio-selected "1 Jansky" (1Jy) sample (RBLs) for which such data were not previously…

Astrophysics · Physics 2009-11-06 Travis A. Rector , John T. Stocke

Observations at millimetre wavelengths are presented for a representative sample of 22 X-ray-selected BL Lac objects (XBLs). This sample comprises 19 High-energy cutoff BL Lacs objects (HBLs), 1 Low-energy cutoff BL Lac object (LBL) and 2…

Astrophysics · Physics 2009-10-31 J. A. Stevens , W. K. Gear

The advent of large area deep radio and X-ray surveys is leading to the creation of many new BL Lac samples. In particular, the ROSAT All-Sky, Green Bank and FIRST surveys are proving to be rich sources of new BL Lacs. We will discuss the…

We present deep radio images at 1.4 GHz of a large and complete sample of BL Lacertae objects (BL Lacs) selected from the Deep X-ray Radio Blazar Survey (DXRBS). We have observed 24 northern sources with the Very Large Array (VLA) in both…

Astrophysics · Physics 2009-11-13 Hermine Landt , Hayley E. Bignall

{Abridged} We report the discovery of six compact, starburst galaxy candidates with redshifts 2.3 < z < 2.8 and r-band magnitudes 19.8-20.5 in the Quasar Catalog of the Sloan Digital Sky Survey First Data Release (SDSS DR1). The SDSS…

Astrophysics · Physics 2009-11-10 Misty C. Bentz , Patrick S. Osmer , David H. Weinberg

We have optically identified a sample of 56 featureless continuum objects without significant proper motion from the 2dF QSO Redshift Survey (2QZ). The steep number--magnitude relation of the sample, $n(\bj) \propto 10^{0.7\bj}$, is similar…

We present a radio/optical study of a sample of BL Lac objects at arcsecond and milliarcsecond resolution. The sample consists of 30 nearby (z<0.2) BL Lacs, mostly X-ray selected. These nearby objects are weak in the radio, yet we have…

Astrophysics · Physics 2007-05-23 M. Giroletti , G. Giovannini , G. B. Taylor , R. Falomo

The origin of broad-absorption-line quasars (BAL QSOs) is still an open issue. Accounting for ~20% of the QSO population, these objects present broad absorption lines in their optical spectra generated from outflows with velocities up to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 G. Bruni , K. -H. Mack , E. Salerno , F. M. Montenegro-Montes , R. Carballo , C. R. Benn , J. I. González-Serrano , J. Holt , F. Jiménez-Luján

We present a new well defined sample of BL Lac objects selected from the ROSAT All-Sky Survey (RASS). The sample consists of 39 objects with 35 forming a flux limited sample down to f_X = 8 x 10^{-13} cgs, redshifts are known for 33 objects…

Astrophysics · Physics 2007-05-23 N. Bade , V. Beckmann , N. G. Douglas , P. D. Barthel , D. Engels , L. Cordis , P. Nass , W. Voges

We investigate the nature of the BL Lac candidates in the northern part of the 2BL sample (\cite{Londish02}) searching for optical variability by means of $R_C$ band photometry with the Asiago 1.8 and Loiano 1.5 meter telescopes during…

Astrophysics · Physics 2009-11-10 R. Nesci , S. Sclavi , E. Massaro

We investigate the nature of low-luminosity radio-loud active galactic nuclei (RLAGN) selected from the LOFAR Two-metre Sky Survey (LoTSS) first data release (DR1). Using optical, mid-infrared, and radio data, we have conservatively…

Astrophysics of Galaxies · Physics 2024-03-01 J. Chilufya , M. J. Hardcastle , J. C. S. Pierce , J. H. Croston , B. Mingo , X. Zheng , R. D. Baldi , H. J. A. Röttgering

In a spectroscopic follow-up to the VLA FIRST survey, the FIRST Bright Quasar Survey (FBQS) has found 29 radio-selected broad absorption line (BAL) quasars. This sample provides the first opportunity to study the properties of…

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

A sample of 312 low-frequency peaked BL Lacertae objects (LBLs) and 694 flat spectrum radio quasars (FSRQs) with the parameters both redshift and $\gamma$-ray photon spectral index ($\Gamma _\gamma$) is compiled from the active galactic…

High Energy Astrophysical Phenomena · Physics 2025-03-31 S. Liang , W. G. Yang , Y. G. Zheng , S. J. Kang

We present a new sample of 30 nearby (z<0.2) BL Lacs, selected to study the nuclear as well as the large scale properties of low power radio sources. In this first paper, we show and discuss new radio data taken with the VLA (19 objects at…

Astrophysics · Physics 2009-11-10 M. Giroletti , G. Giovannini , G. B. Taylor , R. Falomo

We have discovered two low-ionization broad absorption line quasars in programs to obtain optical spectra for radio-selected quasar candidates from the VLA FIRST Survey (Becker, White, & Helfand 1995). Both belong to the extremely rare…

We present updated and complete radio, optical and X-ray data for BL Lacs in the Einstein Medium Sensitivity Survey (EMSS). The complete "M91" sample first presented in Morris et al. is updated to include 26 BL Lacs in total and we define a…

Astrophysics · Physics 2009-10-31 T. A. Rector , J. T. Stocke , E. S. Perlman , S. L. Morris , I. M. Gioia

We have observed 28 sources selected from the 1Jy sample of BL Lac objects (Stickel et al. 1991) with the Very Large Array (VLA) in A, B and D configurations at 1.36, 1.66 and 4.85 GHz, and/or with the Westerbork Synthesis Radio Telescope…

Astrophysics · Physics 2009-10-31 P. Cassaro , C. Stanghellini , M. Bondi , D. Dallacasa , R. Della Ceca , R. A. Zappala`