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Remnant radio-loud AGN in the Herschel-ATLAS field
(2018-04-21)
Only a small fraction of observed active galactic nuclei (AGN) display large-scale radio emission associated with jets, yet these radio-loud AGN have become increasingly important in models of galaxy evolution. In determining ...
LOFAR-Boötes : Properties of high- and low-excitation radio galaxies at 0.5 < z < 2.0
(2018-04-11)
This paper presents a study of the redshift evolution of radio-loud active galactic nuclei (AGN) as a function of the properties of their galaxy hosts in the Boötes field. To achieve this we match low-frequency radio sources ...
A simulation-based analytic model of radio galaxies
(2018-04-01)
I derive and discuss a simple semi-analytical model of the evolution of powerful radio galaxies which is not based on assumptions of self-similar growth, but rather implements some insights about the dynamics and energetics ...
LOFAR reveals the giant : A low-frequency radio continuum study of the outflow in the nearby FR I radio galaxy 3C 31
(2018-03-11)
We present a deep, low-frequency radio continuum study of the nearby Fanaroff-Riley class I (FR I) radio galaxy 3C 31 using a combination of LOw Frequency ARray (LOFAR; 30-85 and 115-178 MHz), Very Large Array (VLA; 290-420 ...
Studying the late evolution of a radio-loud AGN in a galaxy group with LOFAR
(2018-03-11)
Feedback by radio-loud active galactic nuclei (AGNs) in galaxy groups is not fully understood. Open questions include the duty cycle of theAGN, the spatial extent of the radio lobes, the effect they have on the intragroup ...
Faceting for direction-dependent spectral deconvolution
(2018-03-01)
The new generation of radio interferometers is characterized by high sensitivity, wide fields of view and large fractional bandwidth. To synthesize the deepest images enabled by the high dynamic range of these instruments ...
An X-ray survey of the 2 Jy sample - II. X-ray emission from extended structures
(2017-09-21)
The 2 Jy sample is a survey of radio galaxies with flux densities above 2 Jy at 2.7 GHz. As part of our ongoing work on the southern subset of 2 Jy sources, in paper I of this series we analysed the X-ray cores of the ...
A new method for finding and characterizing galaxy groups via low-frequency radio surveys
(2017-09-11)
We describe a new method for identifying and characterizing the thermodynamic state of large samples of evolved galaxy groups at high redshifts using high-resolution, low-frequency radio surveys, such as those that will ...
LOFAR imaging of Cygnus A - direct detection of a turnover in the hotspot radio spectra
(2016-12-01)
The low-frequency radio spectra of the hotspots within powerful radio galaxies can provide valuable information about the physical processes operating at the site of the jet termination. These processes are responsible for ...