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Duty cycle of the radio galaxy B2 0258+35
(2018-10-11)
Context. Radio loud active galactic nuclei (AGN) are episodic in nature, cycling through periods of activity and quiescence. The study of this duty cycle has recently gained new relevance because of the importance of AGN ...
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 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 ...
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 ...
Radiative age mapping of the remnant radio galaxy B2 0924+30 : The LOFAR perspective
(2017-04-01)
We have observed the steep spectrum radio source B2 0924+30 using the LOw Frequency ARray (LOFAR) telescope. Hosted by a z = 0.026 elliptical galaxy, it has a relatively large angular size of 12′ (corresponding to 360 kpc ...
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 ...
The LOFAR Multifrequency Snapshot Sky Survey (MSSS) : I. Survey description and first results
(2015-10-01)
We present the Multifrequency Snapshot Sky Survey (MSSS), the first northern-sky Low Frequency Array (LOFAR) imaging survey. In this introductory paper, we first describe in detail the motivation and design of the survey. ...
Spitzer MID-IR spectroscopy of powerful 2Jy and 3CRR radio galaxies. II : Agn power indicators and unification
(2014-06-20)
It remains uncertain which continuum and emission line diagnostics best indicate the bolometric powers of active galactic nuclei (AGNs), especially given the attenuation caused by the circumnuclear material and the possible ...
An X-ray survey of the 2 Jy sample-I : Is there an accretion mode dichotomy in radio-loud AGN?
(2014-05-01)
We carry out a systematic study of the X-ray emission from the active nuclei of the 0.02 < z< 0.7 2 Jy sample, using Chandra and XMM-Newton observations.We combine our results with those from mid-infrared, optical emission-line ...