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

200 papers

Blazars exhibit flux and spectral variations of largest amplitude at the highest frequencies. Therefore, monitoring their variability at X- and gamma-rays is the most effective tool to peer into the mighty powerhouse of these sources. High…

Astrophysics · Physics 2007-05-23 Elena Pian

In this paper we show an application of the Minimum Spanning Tree (MST) clustering method to the high-energy gamma-ray sky observed at energies higher than 10 GeV in 6.3 years by the Fermi-Large Area Telescope. We report the detection of 19…

High Energy Astrophysical Phenomena · Physics 2016-05-03 R. Campana , E. Massaro , E. Bernieri , Q. D'Amato

We present the results on the cosmological evolution of BL Lac objects as derived from a statistically complete sample of 44 BL Lacs selected from the X-ray bright tail of the REX survey. With this sample, we have investigated the…

Astrophysics · Physics 2007-05-23 A. Caccianiga , T. Maccacaro , A. Wolter , R. Della Ceca , I. M. Gioia

Blazars are radio-loud active galactic nuclei well known for their non thermal emission spanning a wide range of frequencies. The Roma-BZCAT is, to date, the most comprehensive list of these sources. We performed the cross-match of several…

High Energy Astrophysical Phenomena · Physics 2015-05-04 A. Maselli , F. Massaro , R. D'Abrusco , G. Cusumano , V. La Parola , A. Segreto , G. Tosti

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 describe a uniform all-sky survey of bright blazars, selected primarily by their flat radio spectra, that is designed to provide a large catalog of likely gamma-ray AGN. The defined sample has 1625 targets with radio and X-ray properties…

We study the cosmological evolution of BL Lac objects by applying the Ve/Va analysis to a new sample of 55 objects presented for the first time in this paper. This sample has been selected from the 239 sources with the brightest X-ray flux…

Astrophysics · Physics 2009-11-07 A. Caccianiga , T. Maccacaro , A. Wolter , R. Della Ceca , I. M. Gioia

Understanding the origin of fast radio bursts (FRBs) has become the main science driver of recent dedicated FRB surveys. Between July 2019 and February 2022, we carried out ALERT, an FRB survey at 1370 MHz using the Apertif instrument…

The aim of this white paper is to discuss the observing strategies for the LSST Wide-Fast-Deep that would improve the study of blazars (emission variability, census, environment) and Fast Radio Bursts (FRBs). For blazars, these include the…

Instrumentation and Methods for Astrophysics · Physics 2018-12-10 C. M. Raiteri , M. I. Carnerero , B. Balmaverde , F. D'Ammando , C. Righi , A. Possenti , E. Pian , A. Capetti , M. Villata , M. Giroletti , P. Romano , A. Stamerra , F. Tavecchio , S. Vercellone

We report the discovery of five broad-absorption-line (BAL) QSOs in a complete sample of 111 ultraviolet excess (UVX) QSO candidates also detected in the NRAO VLA Sky Survey. All five BAL QSOs, which include two high-ionization BAL QSOs and…

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

We present statistical analyses of a large homogenous data sample of Fermi-detected blazars thoroughly studied in order to reassess the relationship between flat-spectrum radio quasars (FSRQs) and subclasses of BL Lacertae objects (BL Lacs)…

High Energy Astrophysical Phenomena · Physics 2021-08-18 E. U. Iyida , F. C. Odo , A. E. Chukwude , A. A. Ubachukwu

An equivalent width (EW) based classification may cause the erroneous judgement to the flat spectrum radio quasars (FSRQs) and BL Lacerate objects (BL Lac) due to the diluting the line features by dramatic variations in the jet continuum…

High Energy Astrophysical Phenomena · Physics 2023-08-14 Shi-Ju Kang , Yong-Gang Zheng , Qingwen Wu

We present very long baseline interferometry polarization images of an X-ray selected sample of BL Lacertae objects belonging to the first High Energy Astronomy Observatory (HEAO-1) and the ROSAT-Green Bank (RGB) surveys. These are…

Astrophysics · Physics 2009-11-13 P. Kharb , D. Gabuzda , P. Shastri

Current and future continuum surveys being undertaken by the new generation of radio telescopes are now poised to address many important science questions, ranging from the earliest galaxies, to the physics of nearby AGN, as well as…

Instrumentation and Methods for Astrophysics · Physics 2016-04-25 Jeremy J. Harwood , Raffaella Morganti

The vast majority of extragalactic compact continuum radio sources are associated with star formation or jets from (super)massive black holes and, as such, are more likely to be found in association with starburst galaxies or early-type…

High Energy Astrophysical Phenomena · Physics 2023-12-20 D. Vohl , H. K. Vedantham , J. W. T. Hessels , C. G. Bassa , D. O. Cook , D. L. Kaplan , T. W. Shimwell , C. Zhang

Utilizing the latest and the most sensitive radio and optical catalogs, we completed a new blazar candidate catalog, Blazar Radio and Optical Survey (BROS), which includes 88,211 sources located at declination $\delta > -40^{\circ}$ and…

High Energy Astrophysical Phenomena · Physics 2020-08-04 Ryosuke Itoh , Yousuke Utsumi , Yoshiyuki Inoue , Kouji Ohta , Akihiro Doi , Tomoki Morokuma , Koji S. Kawabata , Yasuyuki T. Tanaka

High-redshift radio sources provide plentiful opportunities for studying the formation and evolution of early galaxies and supermassive black holes. However, the number of known radio-loud active galactic nuclei (AGN) above redshift 4 is…

Astrophysics of Galaxies · Physics 2022-06-29 M. Krezinger , K. Perger , K. É. Gabányi , S. Frey , L. I Gurvits , Zs. Paragi , T. An , Y. Zhang , H. Cao , T. Sbarrato

We have discovered 21 Rotating Radio Transients (RRATs) in data from the Green Bank Telescope (GBT) 350-MHz Drift-scan and the Green Bank North Celestial Cap pulsar surveys using a new candidate sifting algorithm. RRATs are pulsars with…