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Related papers: The Bologna Complete Sample: radio and gamma-ray d…

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In the framework of the TANAMI multi-wavelength and VLBI monitoring, we study the evolution of the parsec-scale radio emission in radio galaxies in the southern hemisphere and their relationship to the $\gamma$-ray properties. In this first…

A complete sample of bright ROSAT sources with hard XRB-like spectra in the Galactic Plane (|b| < 15 deg.) has been tentatively identified with radio sources in the GB6/PMN/NVSS surveys, and subsequently observed with the Australia…

Astrophysics · Physics 2007-05-23 G. S. Tsarevsky , E. P. Pavlenko , R. A. Stathakis , N. S. Kardashev , O. B. Slee

The Fermi Large Area Telescope (Fermi-LAT) has detected more than 7,000 gamma-ray sources, a significant fraction of which are identified as blazars, while a comparable number remain classified as blazars of uncertain type (BCUs) or are…

High Energy Astrophysical Phenomena · Physics 2026-02-03 Saqlain Afroz , Titir Mukherjee , Raj Prince

Since 2008 August the Fermi Large Area Telescope (LAT) has provided continuous coverage of the gamma-ray sky yielding more than 5000 gamma-ray sources, but 54% of the detected sources remain with no certain or unknown association with a low…

High Energy Astrophysical Phenomena · Physics 2020-12-01 Chiaro G. , Kovacevic M. , La Mura G

Blazars are a subclass of active galactic nuclei (AGNs) with extreme observation properties, which is caused by the beaming effect, expressed by a Doppler factor, in a relativistic jet. Doppler factor is an important parameter in the…

High Energy Astrophysical Phenomena · Physics 2020-10-21 Zhiyuan Pei , Junhui Fan , Jianghe Yang , Denis Bastieri

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 the results of our follow-up observation program of gamma-ray sources detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. 26 blazars and 39 sources unidentified at other wavelengths were…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Mai Fujiwara , Yoshiki Matsuoka , Nobuyuki Ienaka

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…

We present the radio detection of 18 BL Lac objects from our survey of over 575 square degrees of sky. These 18 objects are located within 20 arcsec of the X-ray position, of which 11 have a measured red-shift. All candidates are radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 M. W. B. Anderson , M. D. Filipović

We demonstrate for the first time using a robust Bayesian approach to analyse the populations of radio-quiet (RQ) and radio-loud (RL) gamma-ray pulsars. We quantify their differences and obtain their distributions of the radio-cone opening…

High Energy Astrophysical Phenomena · Physics 2018-05-02 Hoi-Fung Yu , Chung Yue Hui , Albert K. H. Kong , Jumpei Takata

The F-GAMMA program is a coordinated effort to investigate the physics of Active Galactic Nuclei (AGNs) via multi-frequency monitoring of {\em Fermi} blazars. The current study is concerned with the broad-band radio spectra composed of…

The launch of the Fermi Gamma-ray Space Telescope has heralded a new era in the study of gamma-ray pulsars. The population of confirmed gamma-ray pulsars has gone from 6-7 to more than 60, and the superb sensitivity of the Large Area…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Paul S. Ray , Pablo M. Saz Parkinson

Aims. eROSITA, on board the Spectrum Roentgen Gamma (SRG) spacecraft, performed its first X-ray all-sky survey (eRASS1) between December 2019 and June 2020. It detected about 930000 sources, providing us with an unprecedented opportunity…

In this study we define a new sample of distant powerful radio galaxies in order to study their host-galaxy properties and provide targets for future observations of HI absorption with new radio telescopes and to understand the fuelling and…

Astrophysics of Galaxies · Physics 2019-09-25 Takalani Marubini , Matt J. Jarvis , Stephen Fine , Tom Mauch , Kim McAlpine , Matthew Prescott

We performed time-resolved spectroscopy on a sample of 38 single pulses from 37 gamma-ray bursts detected by the Fermi/Gamma-ray Burst Monitor during its first 9 years of mission. For the first time a fully Bayesian approach is applied. A…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Hoi-Fung Yu , Hüsne Dereli-Bégué , Felix Ryde

We present a study of the radio properties of the dominant early-type galaxies in 26 galaxy groups, the high-richness sub-sample of the Complete Local-volume Groups Sample (CLoGS). Combining new 610 MHz and 235 MHz observations of 21 groups…

Astrophysics of Galaxies · Physics 2018-07-31 Konstantinos Kolokythas , Ewan O'Sullivan , Somak Raychaudhury , Simona Giacintucci , Myriam Gitti , Arif Babul

We present multi-frequency radio continuum VLBI observations of the gravitational lens system B0218+357 carried out using a global VLBI network and the VLBA. The source has been observed with resolutions from 0.2 milliarcsec to 5…

Astrophysics · Physics 2007-05-23 Alok R. Patnaik , Richard W. Porcas

Pulsed gamma rays have been detected with the Fermi Large Area Telescope (LAT) from more than 20 millisecond pulsars (MSPs), some of which were discovered in radio observations of bright, unassociated LAT sources. We have fit the radio and…

High Energy Astrophysical Phenomena · Physics 2011-11-04 Tyrel J. Johnson , Alice K. Harding , Christo Venter

Approximately one-third of the gamma-ray sources in the third Fermi-LAT catalog are unidentified or unassociated with objects at other wavelengths. Observations with Swift-XRT have yielded possible counterparts in $\sim$30% of these source…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Amanpreet Kaur , Abraham D Falcone , Michael D Stroh , Jamie A Kennea , Elizabeth C Ferrara

We present a new sample of 84 large angular size radio galaxies selected from the NRAO VLA Sky Survey. Radio sources with declination above +60 degrees, total flux density greater than 100 mJy at 1.4 GHz and angular size larger than 4…

Astrophysics · Physics 2009-11-06 L. Lara , W. D. Cotton , L. Feretti , G. Giovannini , J. M. Marcaide , I. Marquez , T. Venturi
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