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Low-frequency radio selection finds radio-bright galaxies regardless of the amount of obscuration by gas and dust. We report \chandra\ observations of a complete 178~MHz-selected, and so orientation unbiased, sample of 44 $0.5<z<1$ 3CRR…

As part of an extensive multi-wavelength monitoring campaign, the International Ultraviolet Explorer satellite was used to observe the broad-line radio galaxy 3C 390.3 during the period 1994 December 31 to 1996 March 5. Spectra were…

Due to its brightness and proximity, the radio galaxy 3C 84 (optical counterpart NGC 1275 in the Perseus cluster) has been the target of extensive studies investigating the central parsec region of its active galactic nucleus. In 2003, its…

Astrophysics of Galaxies · Physics 2026-05-28 P. Benke , T. Savolainen , G. Giovannini , Y. Y. Kovalev , G. Bruni , M. M. Lisakov , M. Giroletti , E. Ros

It is shown that the new observed redshift distributions of various flux-limited samples of radio sources in general are consistent with the predictions of two basic evolutionary models published by Condon (1984) and Dunlop and Peacock…

Astrophysics · Physics 2016-01-27 J. Machalski , M. Jamrozy

We present results of temporal and spectral analyses on four XMM-Newton EPIC pn observations of IRAS 17020+4544, a narrow-line Seyfert 1 galaxy with evidence of a radio jet. Analysis of the light curves reveals that this radio-loud source…

High Energy Astrophysical Phenomena · Physics 2020-06-17 A. G. Gonzalez , L. C. Gallo , P. Kosec , A. C. Fabian , W. N. Alston , M. Berton , D. R. Wilkins

This is the third in a series of papers that present observations and results for a sample of 76 ultra-steep-spectrum radio sources designed to find galaxies at high redshift. Here we present multi-frequency radio observations, from the…

Astrophysics · Physics 2009-11-11 I. J. Klamer , R. D. Ekers , J. J. Bryant , R. W. Hunstead , E. M. Sadler , C. De Breuck

We present X-ray intraday variability and power spectral density (PSD) analyses of the longest 23 pointed XMM-Newton observations of the blazar 3C 273 that were taken during 2000 -- 2021. These good time intervals contained between 5 and…

High Energy Astrophysical Phenomena · Physics 2022-02-23 G. S. Pavana Gowtami , Haritma Gaur , Alok C. Gupta , Paul J. Wiita , Mai Liao , Martin Ward

We present an updated estimate of the cosmic radio background (CRB) and the corresponding attenuation lengths for ultra-high energy photons. This new estimate provides associated uncertainties as a function of frequency derived from…

High Energy Astrophysical Phenomena · Physics 2020-11-25 I. C. Niţu , H. T. J. Bevins , J. D. Bray , A. M. M. Scaife

We present the results of a 127 ks XMM-Newton observation of the broad-line radio galaxy 3C 120 performed simultaneously with RXTE. The time-averaged spectrum is Seyfert-like, with a reflection amplitude R ~ 0.5, and a neutral Fe K line…

Astrophysics · Physics 2009-11-10 D. R. Ballantyne , A. C. Fabian , K. Iwasawa

Using JVLA data obtained from high-resolution observations at 5.5 GHz at multiple epochs in 2014 and 2019, we have detected a population of radio variables and transients in the radio bright zone at the Galactic center. With observations…

High Energy Astrophysical Phenomena · Physics 2021-01-06 Jun-Hui Zhao , Mark R. Morris , W. M. Goss

We have used narrow emission line data from the new 7C Redshift Survey to investigate correlations between the narrow-line luminosities and the radio properties of radio galaxies and steep-spectrum quasars. The 7C Redshift Survey is a…

Astrophysics · Physics 2009-10-31 Chris J. Willott , Steve Rawlings , Katherine M. Blundell , Mark Lacy

The blazar 3C 454.3 was revealed by the Fermi Gamma-ray Space Telescope to be in an exceptionally high flux state in July 2008. Accordingly, we performed a multi-wavelength monitoring campaign on this blazar using IR and optical…

Astrophysics · Physics 2011-02-11 E. W. Bonning , C. Bailyn , C. M. Urry , M. Buxton , G. Fossati , L. Maraschi , P. Coppi , R. Scalzo , J. Isler , A. Kaptur

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…

We present optical spectroscopy of all 49 radio galaxies in the 7C-I and 7C-II regions of the 7C Redshift Survey (7CRS). The low-frequency (151 MHz) selected 7CRS sample contains all sources with flux-densities S_151 > 0.5 Jy in three…

We study the radio properties at 1.4 GHz of Seyfert galaxies with strong forbidden high-ionization lines (FHILs), selected from the Sloan Digital Sky Survey - a large-sized sample containing nearly equal proportion of diverse range of…

Astrophysics of Galaxies · Physics 2016-01-05 Dharam V. Lal

Updates are provided on several issues related to Unified Models. A new HST spectrum of Cygnus A confirms the broad MgII emission line, and suggests a very large velocity width as seen in the polarized optical lines. Statistics of the 3CR…

Astrophysics · Physics 2007-05-23 Robert Antonucci

Two frequency observations, mainly at 1.4 and 5 GHz from the VLA, have been used to study spectral variations along the lobes of some nearby low luminosity radio galaxies that constitute a representative sample selected from the B2…

Astrophysics · Physics 2007-05-23 P. Parma , M. Murgia , R. Morganti , A. Capetti , H. R. de Ruiter , R. Fanti

We present radio observations at frequencies ranging from 240 to 8460 MHz of the radio galaxy 4C29.30 (J0840+2949) using the Giant Metrewave Radio Telescope (GMRT), the Very Large Array (VLA) and the Effelsberg telescope. We report the…

Astrophysics · Physics 2008-11-26 M. Jamrozy , C. Konar , D. J. Saikia , L. Stawarz , K. -H. Mack , A. Siemiginowska

We present observations of a complete sub-sample of 20 radio galaxies from the Third Cambridge Catalog (3C) with redshift <0.3 obtained from VLT/MUSE optical integral field spectrograph. These data have been obtained as part of the survey…