English
Related papers

Related papers: Sub-parsec scale imaging of Centaurus A

200 papers

Centaurus A, the closest active galaxy, has been detected from radio to high-energy gamma-rays. The synchrotron radiation by extremely high energy protons may be a suitable mechanism to explain the MeV to GeV emission detected by the…

High Energy Astrophysical Phenomena · Physics 2015-05-13 M. Orellana , G. E. Romero

We have used the VLBA at 5 GHz to observe all galaxies with nuclear radio flux densities above 3.5 mJy found in a VLA survey at 15 GHz of a sample of nearby LINER galaxies. All galaxies were detected revealing high brightness temperature…

Astrophysics · Physics 2009-10-31 Heino Falcke , Neil M. Nagar , Andrew S. Wilson , James S. Ulvestad

We have compared the radio emission from a sample of parsec-scale AGN jets as measured by the VLBA at 15 GHz, with their associated gamma-ray properties that are reported in the Fermi LAT 3-month bright source list. We find in our…

Radio-loud active galactic nuclei (AGNs), hosting powerful relativistic jet outflows, provide an excellent laboratory for studying jet physics. Very long baseline interferometry (VLBI) enables high-resolution imaging on milli-arcsecond…

High Energy Astrophysical Phenomena · Physics 2018-02-07 X. -P. Cheng , T. An , X. -Y. Hong , J. Yang , P. Mohan , K. I. Kellermann , M. L. Lister , S. Frey , W. Zhao , Z. -L. Zhang , X. -C. Wu , X. -F. Li , Y. -K. Zhang

Motivated by the detection of a hardening in the gamma-ray spectrum of the radio galaxy Centaurus A, we have analysed ~10 years of Fermi-LAT observations of 26 radio galaxies to search for similar spectral features. We find that the…

High Energy Astrophysical Phenomena · Physics 2020-01-14 Cameron B. Rulten , Anthony M. Brown , Paula M. Chadwick

We have used the VLBA at 15 GHz to image the structure of 132 strong compact AGN and quasars with a resolution better than one milliarcsecond and a dynamic range typically exceeding 1000 to 1. These observations were made as part of a…

Astrophysics · Physics 2009-10-30 K. I. Kellermann , R. C. Vermeulen , J. A. Zensus , M. H. Cohen

Relativistic jets in AGN in general, and in blazars in particular, are the most energetic and among the most powerful astrophysical objects known so far. Their relativistic nature provides them with the ability to emit profusely at all…

High Energy Astrophysical Phenomena · Physics 2012-10-09 Ivan Agudo , Alan P. Marscher , Svetlana G. Jorstad , Jose L. Gomez

We investigate the Fermi LAT gamma-ray and 15 GHz VLBA radio properties of a joint gamma-ray- and radio-selected sample of AGNs obtained during the first 11 months of the Fermi mission (2008 Aug 4 - 2009 Jul 5). Our sample contains the…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-15 M. L. Lister , M. Aller , H. Aller , T. Hovatta , K. I. Kellermann , Y. Y. Kovalev , E. T. Meyer , A. B. Pushkarev , E. Ros , M. Ackermann , E. Antolini , L. Baldini , J. Ballet , G. Barbiellini , D. Bastieri , K. Bechtol , R. Bellazzini , B. Berenji , R. D. Blandford , E. D. Bloom , M. Boeck , E. Bonamente , A. W. Borgland , J. Bregeon , M. Brigida , P. Bruel , R. Buehler , S. Buson , G. A. Caliandro , R. A. Cameron , P. A. Caraveo , J. M. Casandjian , E. Cavazzuti , C. Cecchi , C. S. Chang , E. Charles , A. Chekhtman , C. C. Cheung , J. Chiang , S. Ciprini , R. Claus , J. Cohen-Tanugi , J. Conrad , S. Cutini , F. de Palma , C. D. Dermer , E. do Couto e Silva , P. S. Drell , A. Drlica-Wagner , C. Favuzzi , S. J. Fegan , E. C. Ferrara , J. Finke , W. B. Focke , P. Fortin , Y. Fukazawa , P. Fusco , F. Gargano , D. Gasparrini , N. Gehrels , S. Germani , N. Giglietto , F. Giordano , M. Giroletti , T. Glanzman , G. Godfrey , I. A. Grenier , S. Guiriec , D. Hadasch , M. Hayashida , E. Hays , D. Horan , R. E. Hughes , G. Jóhannesson , A. S. Johnson , M. Kadler , H. Katagiri , J. Kataoka , J. Knödlseder , M. Kuss , J. Lande , F. Longo , F. Loparco , B. Lott , M. N. Lovellette , P. Lubrano , G. M. Madejski , M. N. Mazziotta , W. McConville , J. E. McEnery , J. Mehault , P. F. Michelson , T. Mizuno , C. Monte , M. E. Monzani , A. Morselli , I. V. Moskalenko , S. Murgia , M. Naumann-Godo , S. Nishino , P. L. Nolan , J. P. Norris , E. Nuss , M. Ohno , T. Ohsugi , A. Okumura , N. Omodei , E. Orlando , M. Ozaki , D. Paneque , D. Parent , M. Pesce-Rollins , M. Pierbattista , F. Piron , G. Pivato , S. Rainò , A. Readhead , A. Reimer , O. Reimer , J. L. Richards , S. Ritz , H. F. -W. Sadrozinski , C. Sgrò , M. S. Shaw , E. J. Siskind , G. Spandre , P. Spinelli , H. Takahashi , T. Tanaka , J. G. Thayer , J. B. Thayer , D. J. Thompson , G. Tosti , A. Tramacere , E. Troja , T. L. Usher , J. Vandenbroucke , V. Vasileiou , G. Vianello , V. Vitale , A. P. Waite , P. Wang , B. L. Winer , K. S. Wood , S. Zimmer

3C 216 is an extragalactic radio source classified as a compact steep spectrum (CSS) object, associated with the source 4FGL J0910.0+4257 detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. The source…

High Energy Astrophysical Phenomena · Physics 2025-06-11 Federica Giacchino , Giovanni La Mura , Stefano Ciprini , Dario Gasparrini , Marcello Giroletti , Marco Laurenti

Over the past few decades, our knowledge of jets produced by active galactic nuclei (AGN) has greatly progressed thanks to the development of very-long-baseline interferometry (VLBI). Nevertheless, the crucial mechanisms involved in the…

High Energy Astrophysical Phenomena · Physics 2017-11-22 B. Boccardi , T. P. Krichbaum , E. Ros , J. A. Zensus

We report observations at mid-infrared and sub-millimeter wavelengths of Centaurus A (CenA, NGC 5128), the giant elliptical galaxy that harbors the closest radio loud Active Galactic Nucleus (AGN) to Earth. The dust emission from the deep…

We present the results from the first large (>100 source) 3.5 mm polarimetric survey of radio loud active galactic nuclei (AGN). The I, Q, U, and V Stokes parameter observations were performed with the XPOL polarimeter at the IRAM 30m…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 I. Agudo , C. Thum , H. Wiesemeyer , T. P. Krichbaum

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…

Alpha Centauri A is the closest solar-type star to the Sun and offers an excellent opportunity to detect the thermal emission of a mature planet heated by its host star. The MIRI coronagraph on JWST can search the 1-3 AU (1"-2") region…

Imaging relativistic jets in active galactic nuclei (AGN) at angular resolution significantly surpassing that of the ground-based VLBI at centimetre wavelengths is one of the key science objectives of the RadioAstron space-VLBI mission.…

Astrophysics of Galaxies · Physics 2020-01-10 Gabriele Bruni , Tuomas Savolainen , Jose Luis Gómez , Andrei P. Lobanov , Yuri Y. Kovalev

We analyze the correlation of the positions of gamma-ray sources in the Fermi Large Area Telescope First Source Catalog (1FGL) and the First LAT Active Galactic Nuclei (AGN) Catalog (1LAC) with the arrival directions of ultra-high-energy…

High Energy Astrophysical Phenomena · Physics 2014-11-21 Rodrigo S. Nemmen , Charles Bonatto , Thaisa Storchi-Bergmann

The $\gamma$-ray production mechanism and its localization in blazars are still a matter of debate. The main goal of this paper is to constrain the location of the high-energy emission in the blazar TXS 2013+370 and to study the physical…

Astrophysics of Galaxies · Physics 2020-02-19 E. Traianou , T. P. Krichbaum , B. Boccardi , R. Angioni , B. Rani , J. Liu , E. Ros , U. Bach , K. V. Sokolovsky , S. Kiehlmann , M. Gurwell , J. A. Zensus

We report the detection of a gamma-ray spectral line at approximately 1.5 GeV in three active galactic nuclei (AGN) using 17 years of Fermi-LAT observations. The sample includes both blazars (with relativistic jets directed toward Earth)…

High Energy Astrophysical Phenomena · Physics 2026-04-02 Shi-Ju Kang , Yue Yin , Yong-Gang Zheng , Qingwen Wu

We present deep radio images of the inner 50 kpc of Centaurus A, taken with the Karl G. Jansky Very Large Array (VLA) at 90cm. We focus on the Transition Regions between the inner galaxy - including the active nucleus, inner radio lobes,…

Astrophysics of Galaxies · Physics 2015-06-23 Susan G. Neff , Jean A. Eilek , Frazer N. Owen

We present the first direct imaging of what may be the thick torus in the active galactic nucleus (AGN) of the archetype powerful radio galaxy Cygnus A, using the Jansky Very Large Array (VLA) at 18 GHz to 48 GHz, with a resolution down to…

High Energy Astrophysical Phenomena · Physics 2019-07-17 C. L. Carilli , R. A. Perley , V. Dhawan , D. A. Perley
‹ Prev 1 3 4 5 6 7 10 Next ›