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3C 84 (NGC 1275) is a well-studied mis-aligned Active Galactic Nucleus (AGN), which has been active in Gamma rays since at least 2008. We have monitored the source at four wavelengths (14 mm, 7 mm, 3 mm and 2 mm) using the Korean VLBI…

3C 84 is a nearby Active Galactic Nucleus (AGN) that is unique in that is believed that we are observing near the true jet launching region - unlike blazars. The source is active in Gamma rays and has been detected with Fermi since its…

High Energy Astrophysical Phenomena · Physics 2018-02-09 Jeffrey A. Hodgson , Bindu Rani , Junghwan Oh

We present results of single-epoch very long baseline interferometry (VLBI) observations of gamma-ray bright active galactic nuclei (AGNs) using the Korean VLBI Network (KVN) at 22, 43, 86, and 129~GHz bands, which are part of a KVN key…

The radio galaxy 3C84 is a representative of gamma-ray-bright misaligned active galactic nuclei (AGN) and one of the best laboratories to study the radio properties of subparsec scale jets. We discuss here the past and present activity of…

We present six-year multi-wavelength monitoring result for broad-line radio galaxy 3C 120. The source was sporadically detected by Fermi-LAT and after the MeV/GeV gamma-ray detection the 43 GHz radio core brightened and a knot ejected from…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Y. T. Tanaka , A. Doi , Y. Inoue , C. C. Cheung , L. Stawarz , Y. Fukazawa , M. A. Gurwell , M. Tahara , J. Kataoka , R. Itoh

Active galactic nuclei (AGNs) exhibit variability across the entire electromagnetic spectrum with distinct flaring episodes at different frequencies. The high sensitivity and nearly uniform sky coverage of the Large Area Telescope on board…

High Energy Astrophysical Phenomena · Physics 2022-03-02 Filippo D'Ammando

The Broad Line Radio Galaxy 3C 111, characterized by a Fanaroff-Riley II (FRII) radio morphology, is one of the sources of the Misaligned Active Galactic Nuclei sample, consisting of Radio Galaxies and Steep Spectrum Radio Quasars, recently…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Paola Grandi , Eleonora Torresi , Carlo Stanghellini

We present the results of multi-epoch, multi-frequency monitoring of a blazar 4C +29.45, which was regularly monitored as part of the Interferometric Monitoring of GAmma-ray Bright Active Galactic Nuclei (iMOGABA) program - a key science…

High Energy Astrophysical Phenomena · Physics 2021-07-21 S. Kang , S. -S. Lee , J. Hodgson , J. -C. Algaba , J. W. Lee , J. -Y. Kim , J. Park , M. Kino , D. Kim , S. Trippe

Ever since the discovery by the Fermi mission that active galactic nuclei (AGN) produce copious amounts of high-energy emission, its origin has remained elusive. Using high-frequency radio interferometry (VLBI) polarization imaging, we…

High Energy Astrophysical Phenomena · Physics 2018-05-15 B. Rani , S. G. Jorstad , A. P. Marscher

The radio galaxy 3C 84 is a representative of gamma-ray-bright misaligned active galactic nuclei (AGNs) and one of the best laboratories to study the radio properties of the sub-pc jet in connection with the gamma-ray emission. In order to…

We analyze the long-term evolution of the fluxes of six active galactic nuclei (AGN) - 0923+392, 3C 111, 3C 273, 3C 345, 3C 454.3, and 3C 84 - in the frequency range 80-267 GHz using archival calibration data of the IRAM Plateau de Bure…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 S. Trippe , M. Krips , V. Pietu , R. Neri , J. M. Winters , F. Gueth , M. Bremer , P. Salome , R. Moreno , J. Boissier , F. Fontani

Dual-Active Galactic Nuclei (AGN) are a natural consequence of the hierarchical structure formation scenario, and can provide an important test of various models for black hole growth. However, due to their rarity and difficulty to find at…

Astrophysics of Galaxies · Physics 2021-09-22 C. S. Mangat , J. P. McKean , R. Brilenkov , P. Hartley , H. R. Stacey , S. Vegetti , D. Wen

We present the observational results from the 43-GHz Very Long Baseline Array (VLBA) observations of 124 compact radio-loud active galactic nuclei (AGNs) that were conducted between 2014 November and 2016 May. The typical dimensions of the…

High Energy Astrophysical Phenomena · Physics 2020-07-07 X. -P. Cheng , T. An , S. Frey , X. -Y. Hong , X. He , K. I. Kellermann , M. L. Lister , B. -Q. Lao , X. -F. Li , P. Mohan , J. Yang , X. -C. Wu , Z. -L. Zhang , Y. -K. Zhang , W. Zhao

As a critical part of the Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry (TANAMI) program, in November 2007 the Australia Telescope Compact Array (ATCA) started monitoring the radio spectra of a sample of…

High Energy Astrophysical Phenomena · Physics 2012-05-14 J. Stevens , P. G. Edwards , R. Ojha , M. Kadler , F. Hungwe , M. Dutka , S. Tingay , J. P. Macquart , A. Moin , J. Lovell , J. Blanchard

Active Galactic Nuclei (AGN) sources feature supermassive black holes that launch relativistic plasma jets. They are key $\gamma$-ray sources providing a unique laboratory for studying extreme particle acceleration and plasma physics.…

High Energy Astrophysical Phenomena · Physics 2026-02-03 Luana Passos-Reis , Elisabete M. de Gouveia Dal Pino , Tarek Hassan , Santiago Pita , Alberto Domínguez

We conducted millimeter continuum observations for samples of nearby early-type galaxies (21 sources) and nearby low-luminosity active galactic nuclei (LLAGN; 16 sources) at 100 GHz (3 mm) using the Nobeyama Millimeter Array (NMA). In…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Akihiro Doi , Kouichiro Nakanishi , Hiroshi Nagai , Kotaro Kohno , Seiji Kameno

We present results of long-term multi-wavelength polarization observations of the powerful blazar 3C~279 after its $\gamma$-ray flare on 2013~December 20. We followed up this flare with single-dish polarization observations using two 21-m…

Astrophysics of Galaxies · Physics 2015-11-11 Sincheol Kang , Sang-Sung Lee , Do-Young Byun

Within the MOJAVE VLBA program (Monitoring of Jets in AGN with VLBA Experiments), we have accumulated observational data at 15 GHz for hundreds of jets in $\gamma$-ray bright active galactic nuclei since the beginning of the Fermi…

High Energy Astrophysical Phenomena · Physics 2021-12-23 I. G. Kramarenko , A. B. Pushkarev , Y. Y. Kovalev , M. L. Lister , T. Hovatta , T. Savolainen

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
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