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Related papers: Unifying B2 radio galaxies with BL Lac objects

200 papers

HST observations have shown that low-redshift 3CR radio galaxies often exhibit a point-like optical component positionally coincident with the GHz-frequency radio core. In this paper we discuss the correlation between the luminosities of…

Astrophysics · Physics 2009-10-31 M. J. Hardcastle , D. M. Worrall

Snapshot images of about 100 BL Lac objects were obtained with WFPC2 on HST. Sources from various samples, in the redshift range 0.05 to 1.2, were observed and 61 resolved (51 with known z). The high resolution and homogeneity of the images…

Astrophysics · Physics 2016-08-30 R. Falomo , C. Megan Urry , Riccardo Scarpa , Joseph E. Pesce , Aldo Treves

(Abridged) We use a complete sample of active galactic nuclei (AGN) selected on the basis of relativistically beamed 15 GHz radio flux density to derive the parent radio luminosity function (RLF) of bright radio-selected blazar cores. We…

Astrophysics · Physics 2009-11-13 M. Cara , M. L. Lister

X-shaped radio galaxies are defined by their peculiar large-scale radio morphology. In addition to the classical double-lobed structure they have a pair of low-luminosity wings that straddles the nucleus at almost right angles to the active…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Hermine Landt , Chi C. Cheung , Stephen E. Healey

We present new methods to quantify the AGN population in terms of a multi-dimensional luminosity function that describes the space density of sources as a function of both X-ray and radio luminosity. We compile a sample of 1538 radio and…

High Energy Astrophysical Phenomena · Physics 2025-11-19 Clara M. Pennock , James Aird , Cassandra L. Barlow-Hall

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 propose a scenario where blazars are classified as flat-spectrum radio quasars (FSRQs), BL Lacs, low synchrotron, or high synchrotron peaked objects according to a varying mix of the Doppler boosted radiation from the jet, the emission…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 P. Giommi , P. Padovani , G. Polenta , S. Turriziani , V. D'Elia , S. Piranomonte

Our knowledge of the blazar surface densities and luminosity functions, which are fundamental parameters, relies still on samples at relatively high flux limits. As a result, our understanding of this rare class of active galactic nuclei is…

Astrophysics · Physics 2011-02-11 P. Padovani , P. Giommi , H. Landt , E. S. Perlman

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 performed the the first census of Mpc-scale radio emission to include control fields and quantifiable upper limits for bright X-ray clusters in the range 0.03<z<0.3 . Through reprocessing radio images from the WENSS survey, we…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-15 Lawrence Rudnick , Jeffrey Lemmerman

We use the BD2 sample of gamma-ray bursts (GRBs) based on 5.9 years of BATSE DISCLA data with a variety of models of the luminosity function to derive characteristic GRB luminosities, space densities and redshift distributions. Previously…

Astrophysics · Physics 2009-10-31 Maarten Schmidt

Using a significantly enlarged \textit{Fermi}-LAT BL Lac objects (BL Lacs) sample, we construct the gamma-ray luminosity function (GLF) of BL Lacs, by the joint use of the space density distribution and source counts distribution. We use…

High Energy Astrophysical Phenomena · Physics 2019-10-02 Yankun Qu , Houdun Zeng , Dahai Yan

We investigate the correlation between far-infrared (FIR) and radio luminosities in distant galaxies, a lynchpin of modern astronomy. We use data from the Balloon-borne Large Aperture Submillimetre Telescope (BLAST), Spitzer, the Large Apex…

We collect a sample of 78 Fermi detected blazars with broad line region (BLR) data and the quasi-simultaneous multi-wave band data. By analyzing the sample, we find: (1) For whole blazar sample, there exist significant correlations between…

High Energy Astrophysical Phenomena · Physics 2017-09-20 Zerui Wang , Rui Xue , Zhaohua Xie , Leiming Du , Tingfeng Yi , Yunbing Xu , Wenguang Liu

The past 20 years have seen phenomenal progress in our understanding of BL Lac objects. They form part of the blazar class, which are radio-loud AGN whose relativistic jets are aligned along our line of sight. Several critical milestones…

Astrophysics · Physics 2007-05-23 C. Megan Urry

We present spectroscopic observations of a complete sub-sample of 13 low-luminosity radio galaxies selected from the 2Jy sample. The underlying continuum in these sources is carefully modelled in order to make a much-needed comparison…

Astrophysics · Physics 2009-11-10 K. A. Wills , R. Morganti , C. N. Tadhunter , T. G. Robinson , M. Villar-Martin

Based on well-grounded Galactic neutron star populations formed from radio pulsar population syntheses of canonical pulsars (CPs) and millisecond pulsars (MSPs), we use the latest Fermi-LAT catalog (4FGL-DR4) to investigate the implications…

High Energy Astrophysical Phenomena · Physics 2025-06-23 Shawaiz Tabassum , Duncan Lorimer

We present simulated millimeter-wavelength maps and catalogs of radio galaxies across the full sky that trace the nonlinear clustering and evolution of dark matter halos from the Websky simulation at $z<4.6$ and $M_{\rm halo}>10^{12}…

Astrophysics of Galaxies · Physics 2022-08-24 Zack Li , Giuseppe Puglisi , Mathew S. Madhavacheril , Marcelo A. Alvarez

Hubble Space Telescope (HST) observations provide a novel way of testing unified models for FR I radio sources and BL Lac objects. The detection of extended dust discs in some radio galaxies provides information on their jet orientation.…

Astrophysics · Physics 2009-10-31 Alessandro Capetti , Annalisa Celotti

Fermi has provided the largest sample of gamma-ray selected blazars to date. In this work we use a uniformly selected set of 211 BL Lacertae (BL Lac) objects detected by it Fermi during its first year of operation. We have obtained redshift…