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Untangling cosmic magnetic fields: Faraday tomography at metre wavelengths with LOFAR
(2018-11-29)
The technique of Faraday tomography is a key tool for the study ofmagnetised plasmas in the new era of broadband radio-polarisation observations. In particular, observations at metre wavelengths provide significantly better ...
Focusing on the extended X-ray emission in 3C 459 with a Chandra follow-up observation
(2018-11-09)
Aims. We investigated the X-ray emission properties of the powerful radio galaxy 3C 459 revealed by a recent Chandra follow-up observation carried out in October 2014 with a 62 ks exposure. Methods. We performed an X-ray ...
LOFAR MSSS: Flattening low-frequency radio continuum spectra of nearby galaxies
(2018-11-07)
Aims. The shape of low-frequency radio continuum spectra of normal galaxies is not well understood, the key question being the role of physical processes such as thermal absorption in shaping them. In this work we take ...
A catalogue of faint local radio AGN and the properties of their host galaxies
(2018-09-01)
We present a catalogue of 2210 local ( z < 0.1) galaxies that contain faint active galactic nuclei (AGN). We select these objects by identifying galaxies that exhibit a significant excess in their radio luminosities, ...
The X-ray Ribs Within the Cocoon Shock of Cygnus A
(2018-06-01)
We use new and archival Chandra observations of Cygnus A, totalling ~1.9Ms, to investigate the distribution and temperature structure of gas lying within the projected extent of the cocoon shock and exhibiting a rib-like ...
Particle content, radio-galaxy morphology and jet power : all radio-loud AGN are not equal
(2018-05-11)
Ongoing and future radio surveys aim to trace the evolution of black hole growth and feedback from active galactic nuclei (AGNs) throughout cosmic time; however, there remain major uncertainties in translating radio ...
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 ...
Interpreting radiative efficiency in radio-loud AGNs
(2018-04-05)
Radiative efficiency in radio-loud active galactic nuclei is governed by the accretion rate onto the central black hole rather than directly by the type of accreted matter; while it correlates with real differences in host ...
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 ...