English
Related papers

Related papers: Gamma-Rays from Radio Galaxies: Fermi-Lat Observat…

200 papers

Radio-loud sources with blazar-like properties, but having a jet that does not directly point in the direction of the observer are among the most interesting classes of gamma-ray emitters. These sources are known as Misaligned Active…

Astrophysics of Galaxies · Physics 2020-07-30 G. Chiaro , G. La Mura , A. Dominguez , S. Bisogni

The advent of new all-sky radio surveys such as the VLA Sky Survey (VLASS) and the Rapid ASKAP Continuum Survey (RACS), performed with the latest generation radio telescopes, is opening new possibilities on the classification and study of…

High Energy Astrophysical Phenomena · Physics 2022-04-06 G. Bruni , L. Bassani , M. Persic , Y. Rephaeli , A. Malizia , M. Molina , M. Fiocchi , R. Ricci , M. H. Wieringa , M. Giroletti , F. Panessa , A. Bazzano , P. Ubertini

Misaligned AGN (MAGNs), i.e., radio-loud AGNs with the jet not pointing directly towards us, represent a new class of GeV emitters revealed by the Fermi space telescope. Although they comprise only a small fraction of the high-energy…

High Energy Astrophysical Phenomena · Physics 2017-06-21 R. Angioni , P. Grandi , E. Torresi , C. Vignali , J. Knödlseder

The detection of gamma rays from a small number of Narrow Line Seyfert 1 galaxies by the LAT instrument onboard Fermi seriously challenged our understanding of AGN physics. Among the most important findings associated with their discovery…

High Energy Astrophysical Phenomena · Physics 2013-04-08 E. Angelakis , L. Fuhrmann , I. Myserlis , I. Nestoras , V. Karamanavis , T. P. Krichbaum , J. A. Zensus , N. Marchili , L. Foschini , H. Ungerechts , A. Sievers

Radio and gamma-ray emission from active galactic nuclei (AGN) are thought to share a common origin, related to the ejection phenomena in the vicinity of supermassive black holes. Thanks to its sensitivity, surveying capability, and broad…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-29 M. Giroletti , A. Reimer , L. Fuhrmann , V. Pavlidou , J. L. Richards

Radio galaxies have emerged as a new gamma-ray emitting source class on the extragalactic sky. With their jets misaligned, i.e. not directly pointing towards us, they offer a unique tool to probe some of the fundamental (and otherwise…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Frank M. Rieger

We report on a detailed investigation of the gamma-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reported detections of 3C 120 and 3C 111 in the…

Using high-resolution radio imaging with VLBI techniques, the TANAMI program has been observing the parsec-scale radio jets of southern (declination south of -30{\deg}) gamma-ray bright AGN simultaneously with Fermi/LAT monitoring of their…

Over the past decade, our knowledge of the \gamma-ray sky has been revolutionized by ground- and space-based observatories by detecting photons up to several hundreds of tera-electron volt (TeV) energies. A major population of the…

High Energy Astrophysical Phenomena · Physics 2018-11-05 B. Rani

We perform a multi-band statistical analysis of core-dominated superluminal active galactic nuclei (AGN) detected with Fermi Large Area Telescope (LAT). The detection rate of $\gamma$-ray jets is found to be high for optically bright AGN.…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-14 T. G. Arshakian , J. León-Tavares , J. Torrealba , V. H. Chavushyan

In the first 3.5 years of operations the Fermi LAT detected several sources with daily fluxes brighter than F(E>100MeV) > 10^{-6} ph/cm^2/s, the threshold set by the Fermi Collaboration for issuing an Astronomer Telegram. We focus the…

High Energy Astrophysical Phenomena · Physics 2013-03-13 S. Buson , D. Bastieri , F. D'Ammando , G. Tosti

While observations in the radio band are providing essential information on the innermost structures of relativistic jets in active galactic nuclei (AGN), the recent detection by Fermi of gamma-ray emission from many hundreds of blazars…

High Energy Astrophysical Phenomena · Physics 2015-06-11 G. Giovannini , T. Cheung

We present a catalog of sources of very high energy (E>100 GeV) gamma-rays detected by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope at Galactic latitudes |b|>=10 degrees. We cross-correlate the directions of…

High Energy Astrophysical Phenomena · Physics 2015-05-18 A. Neronov , D. V. Semikoz , Ie. Vovk

Blazars are a small fraction of all extragalactic sources but, unlike other objects, they are strong emitters across the entire electromagnetic spectrum. Recent data in the microwave region of the electromagnetic spectrum have become…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-24 D. Gasparrini , E. Cavazzuti , P. Giommi , C. Pittori , S. Colafrancesco , Fermi-LAT collaboration

We have compared the parsec-scale jet linear polarization properties of the Fermi LAT-detected and non-detected sources in the complete flux-density-limited (MOJAVE-1) sample of highly beamed AGN. Of the 123 MOJAVE sources, 30 were detected…

High Energy Astrophysical Phenomena · Physics 2010-08-23 T. Hovatta , M. L. Lister , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

We report the discovery of gamma-ray emission from two radio-loud narrow-line Seyfert 1 galaxies using data from Fermi/LAT: J0804+3853 (z = 0.211) and J1443+4725 (z = 0.502). The objects were discovered due to singular, separate, and brief…

High Energy Astrophysical Phenomena · Physics 2014-04-29 Joseph R. Eggen , Jeremy D. Maune , H. R. Miller

We considered the fourth catalog of gamma-ray point sources produced by the Fermi Large Area Telescope (LAT) and selected only jetted active galactic nuclei (AGN) or sources with no specific classification, but with a low-frequency…

Radio galaxies are uncommon $\gamma$-ray emitters, and only low redshift radio galaxies are detected with Fermi-LAT. However, they offer potential insights into the emission mechanisms of active galaxies, particularly as the alignment of…

High Energy Astrophysical Phenomena · Physics 2020-06-17 Max Harvey , Cameron B. Rulten , Paula M. Chadwick

Fast Radio Bursts (FRBs) are a mysterious flash phenomenon detected in radio wavelengths with a duration of only a few milliseconds, and they may also have prompt gamma-ray flashes. Here we carry out a blind search for msec-duration…

High Energy Astrophysical Phenomena · Physics 2019-06-07 Shotaro Yamasaki , Tomonori Totani , Norita Kawanaka

It has been suggested that unresolved radio galaxies and radio quasars (sometimes referred to as misaligned active galactic nuclei) could be responsible for a significant fraction of the observed diffuse gamma-ray background. In this study,…

High Energy Astrophysical Phenomena · Physics 2016-08-17 Dan Hooper , Tim Linden , Alejandro Lopez