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Related papers: Four New BL Lac Surveys: Sampling New Populations

200 papers

I present an introductory review text, focusing on recent deep field studies using radio telescopes, including high-resolution, wide-field VLBI observations. The nature of the faint radio source population is discussed, taking into account…

Astrophysics · Physics 2009-11-10 M. A. Garrett

We carried out multi-color optical monitoring of a sample of ten blazars from 2005 to 2011. The sample contains 3 LBLs, 2 IBLs, 4 HBLs, and 1 FSRQ. Our monitoring focused on the long-term variability and the sample included nine BL Lac…

Astrophysics of Galaxies · Physics 2018-08-08 Nankun Meng , Xiaoyuan Zhang , Jianghua Wu , Jun Ma , Xu Zhou

BL Lac objects are known to have compact jets inclined to our line of sight at a small angle, showing prominent radio emission. Two radio-weak BL Lac candidates with no counterparts in current radio surveys were recently reported by Massaro…

Astrophysics of Galaxies · Physics 2018-10-17 Hong-Min Cao , Sándor Frey , Krisztina É. Gabányi , Jun Yang , Lang Cui , Xiao-Yu Hong , Tao An

We compare the variability properties of very high energy gamma-ray emitting BL Lac objects in the optical and radio bands. We use the variability information to distinguish multiple emission components in the jet, to be used as a guidance…

We report on our further analysis of the expanded and revised sample of potential BL Lac objects (the 2BL) optically identified from two catalogues of blue-selected (UV excess) point sources, the 2dF and 6dF QSO Redshift Surveys (2QZ and…

The extragalactic $\gamma$-rays sky observed by Fermi-Large Area Telescope (LAT) is dominated by blazars. In the fourth release of the Fermi-LAT Point Source Catalog (4FGL), are sources showing a multifrequency behavior similar to that of…

I address the need for deep blazar surveys by showing that our current understanding of blazars is based on a relatively small number of intrinsically luminous sources. I then review the on-going deeper surveys, addressing in particular…

Astrophysics · Physics 2007-05-23 Paolo Padovani

BL Lac objects are known to have very energetic jets pointing towards the observer under small viewing angles. Many of these show high luminosity over the whole energy range up to TeV, mostly classified as high-energy peaked BL Lac objects.…

High Energy Astrophysical Phenomena · Physics 2015-06-03 S. Kaufmann , S. J. Wagner , O. Tibolla

We describe the steps involved in performing searches for sources of transient radio emission such as Rotating Radio Transients (RRATs), and present 10 new transient radio sources discovered in a re-analysis of the Parkes Multi-beam Pulsar…

Solar and Stellar Astrophysics · Physics 2015-05-14 E. F. Keane , D. A. Ludovici , R. P. Eatough , M. Kramer , A. G. Lyne , M. A. McLaughlin , B. W. Stappers , .

We present an overview of unbiased studies of diffuse extragalactic radio sources. We use a previously developed filtering technique to remove compact sources from large surveys such as WENSS, WISH, and NVSS and examine the residual diffuse…

Astrophysics · Physics 2009-11-11 Lawrence Rudnick , Kisha M. Delain , Jeffrey A. Lemmerman

We are carrying out a multi-purpose program of high signal to noise optical spectroscopy at medium resolution of 30 BL Lac objects. Here we report the detection of three new redshifts, and the discovery of three misclassified sources. The…

Astrophysics · Physics 2016-08-30 N. Carangelo , R. Falomo , J. Kotilainen , A. Treves , M. -H. Ulrich

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

CMB surveys provide, for free, blindly selected samples of extragalactic radio sources at much higher frequencies than traditional radio surveys. Next-generation, ground-based CMB experiments with arcmin resolution at mm wavelengths will…

We report on 16 BL Lacertae objects that were proposed to be at z > 1. We present spectroscopic observations secured at the 10.4m GTC that allowed us to assess the redshift of these sources. In particular, for five objects we disprove the…

High Energy Astrophysical Phenomena · Physics 2018-07-25 M. Landoni , S. Paiano , R. Falomo , R. Scarpa , A. Treves

Rotating Radio Transients (RRATs) are a new class of neutron stars discovered through the emission of radio bursts. Eleven sources are known up to now, but population studies predict these objects to be more numerous than the normal radio…

Astrophysics · Physics 2015-05-13 Nanda Rea

The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey (VIPS). This large, flux-limited sample of active…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 J. D. Linford , G. B. Taylor , R. Romani , S. E. Healey , J. F. Helmboldt , A. C. S. Readhead , R. Reeves , J. Richards , G. Cotter

We present a new sample of Compact Steep Spectrum (CSS) sources with radio luminosity below 10^26 W/Hz at 1.4 GHz called the low luminosity compact (LLC) objects. The sources have been selected from FIRST survey and observed with MERLIN at…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 M. Kunert-Bajraszewska , M. P. Gawronski , A. Labiano , A. Siemiginowska

A sizeable fraction of gamma-ray burst (GRB) light curves (LCs) features a sequence of peaks, which holds information on the unknown way energy is dissipated into gamma-rays over time. Traditional searches for periodic signals in GRB LCs…

High Energy Astrophysical Phenomena · Physics 2025-05-21 C. Guidorzi , M. Orlandini , R. Maccary , L. Amati , L. Bazzanini , M. Bulla , L. Ferro , F. Frontera , M. Maistrello , W. -J. Tan , A. Tsvetkova , S. L. Xiong , S. N. Zhang

We present VLA and first-epoch VLBA observations that are part of a program to study the parsec-scale radio structure of a sample of fifteen high-energy-peaked BL Lacs (HBLs). The sample was chosen to span the range of logarithmic X-ray to…

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

In this paper, we collect radio and X-ray observations for most Fanaroff-Riley I (FRI) radio galaxies in the Zirbel-Baum radio galaxy sample, and investigate the distribution of the radio-to-X-ray effective spectral index, $\alpha_{rx}$, to…

Astrophysics · Physics 2009-10-31 J. M. Bai , Myung Gyoon Lee
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