Results 11 to 20 of about 40,003 (204)

Active Galactic Nuclei, Radio Jets and Acceleration of UHECRs [PDF]

Nuclear Physics B - Proceedings Supplements, 2008
We present the general properties of the Active Galactic Nuclei (AGNs) and discuss the origin and structure of jets that are associated to a fraction of these objects.
Allen, Biermann, Biermann, Blandford, Cesarsky, Fanaroff, Giannios, Giovannini, Giovannini, Heinz, Hillas, Kang, Kovalev, Ledlow, Lyutikov, Massaglia, Massaglia, Mauch, Milgrom, Nagano, Prieto, Protheroe, Rachen, Rossi, S. Massaglia, Sikora, Urry, Vietri   +27 more
core   +4 more sources

A 3.5mm Polarimetric Survey of Radio-loud Active Galactic Nuclei [PDF]

The Astrophysical Journal Supplement Series, 2010
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 Telescope.
Agudo, I., Krichbaum, T. P., Thum, C., Wiesemeyer, H.   +3 more
core   +2 more sources

Origin of Radio Emission from Nearby Low-Luminosity Active Galactic Nuclei [PDF]

The Astrophysical Journal, 2004
We use the observational data in radio, optical and X-ray wavebands, for a sample of active galactic nuclei (AGNs) with measured black hole masses, to explore the origin of radio emission from nearby low-luminosity active galactic nuclei (LLAGNs).
Falcke H., Ishisaki Y., Qingwen Wu, Schulz H., Stanger V. J., Trinchieri G., Turner T. J., Witt H. J., Xinwu Cao   +8 more
core   +2 more sources

VLBI observations of nearby radio loud Active Galactic Nuclei

Journal of Physics: Conference Series, 2008
We present an update of the parsec scale properties of the Bologna Complete Sample consisting of 95 radio sources from the B2 Catalog of Radio Sources and the Third Cambridge Revised Catalog (3CR), with z < 0.1.
Baum S, Elisabetta Liuzzo, Feretti L, Floyd D J E, Gabriele Giovannini, Giovannini G, Giovannini G, Giovannini G, Gregory B Taylor, Marcello Giroletti   +9 more
core   +3 more sources

The Contribution of Active Galactic Nuclei to the Microjansky Radio Population [PDF]

The Astrophysical Journal, 2009
A X-ray background synthesis model is used to calculate the contribution of Active Galactic Nuclei (AGNs) to the 1.4 GHz number counts between 100 nJy and 10 mJy.
Ballantyne, Ballantyne, Ballantyne, Barger, Bell, Benn, Blundell, Bondi, Brinkmann, D. R. Ballantyne, Donley, Fomalont, Gabor, Grogin ., Heckman, Hickox, Hopkins, Hopkins, Hopkins, Hopkins, Huynh, Kellermann, Kellermann, Kim, La Franca, Lawrence, Longair, Moran, Mushotzky, Napier, Padovani, Pierce, Richards, Schawinski, Schinnerer, Serjeant, Shi, Sikora, Silverman, Silverman, Smolčić, Solomon, Spergel, Terashima, Thompson, Tozzi, Treister, Treister, Tueller, Ueda, Wada, Watabe, White, Wilman, Winter, Yun, Zakamska   +56 more
core   +2 more sources

Investigating the Star Formation Characteristics of Radio Active Galactic Nuclei

The Astrophysical Journal
The coevolution of supermassive black holes and their host galaxies represents a fundamental question in astrophysics. One approach to investigating this question involves comparing the star formation rates (SFRs) of active galactic nuclei (AGNs) with ...
Bojun Zhang, Fan Zou, W. N. Brandt, Shifu Zhu, Nathan Cristello, Qingling Ni, Yongquan Xue, Zhibo Yu   +7 more
doaj   +4 more sources

Deciphering Radio Emissions from Accretion Disk Winds in Radio-quiet Active Galactic Nuclei

The Astrophysical Journal
Unraveling the origins of radio emissions from radio-quiet active galactic nuclei (RQ AGNs) remains a pivotal challenge in astrophysics. One potential source of this radiation is the shock interaction between AGN disk winds and the interstellar medium ...
Tomoya Yamada, Nobuyuki Sakai, Yoshiyuki Inoue, Tomonari Michiyama   +3 more
doaj   +3 more sources

Identifying Radio-active Galactic Nuclei among Radio-emitting Galaxies [PDF]

The Astrophysical Journal, 2021
Abstract Basing our analysis on ROGUE I, a catalog of over 32,000 radio sources associated with optical galaxies, we provide two diagnostics to select the galaxies where the radio emission is dominated by an active galactic nucleus (AGN), referred to in the paper as radio-AGNs. Each of these diagnostics can be applied independently.
D. Kozieł-Wierzbowska, N. Vale Asari, G. Stasińska, F. R. Herpich, M. Sikora, N. Żywucka, A. Goyal   +6 more
openaire   +4 more sources

The radio emission from active galactic nuclei [PDF]

Astronomy & Astrophysics, 2021
Context. For nearly seven decades, astronomers have been studying active galaxies, that is to say, galaxies with actively accreting central supermassive black holes: active galactic nuclei (AGN). A small fraction are characterized by luminous, powerful radio emission: This class is known as radio-loud AGN.
J. F. Radcliffe, P. D. Barthel, M. A. Garrett, R. J. Beswick, A. P. Thomson, T. W. B. Muxlow   +5 more
openaire   +5 more sources

The radio dichotomy of active galactic nuclei [PDF]

Publications of the Astronomical Society of Japan, 2022
Abstract The question of radio dichotomy in active galactic nuclei (AGNs) is still in debate, even though it has been discussed for more than 40 years. In order to solve this old riddle, we collect a sample of AGNs with optical B band and radio 6 cm wavelength data to analyze the radio loudness log R. Our results indicate a separation of
Xiao, Hubing, Zhu, Jingtian, Fu, Liping, Zhang, Shaohua, Fan, Junhui   +4 more
openaire   +2 more sources