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A plethora of diffuse steep spectrum radio sources in Abell 2034 revealed by LOFAR
(2016-06-11)
With Low-Frequency Array (LOFAR) observations, we have discovered a diverse assembly of steep spectrum emission that is apparently associated with the intra cluster medium (ICM) of the merging galaxy cluster Abell 2034. ...
X-ray properties of the Youngest Radio Sources and their Environments
(2016-05-23)
We present the first results from our X-ray study of young radio sources classified as compact symmetric objects (CSOs). Using the Chandra X-ray Observatory we observed six CSOs for the first time in X-rays, and re-observed ...
Galaxy And Mass Assembly (GAMA) : The 325-MHz Radio Luminosity Function of AGN and Star Forming Galaxies
(2016-03-21)
Measurement of the evolution of both active galactic nuclei (AGN) and star-formation in galaxies underpins our understanding of galaxy evolution over cosmic time. Radio continuum observations can provide key information ...
LOFAR facet calibration
(2016-03-07)
LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides ...
LOFAR MSSS: Detection of a low-frequency radio transient in 400 hrs of monitoring of the North Celestial Pole
(2016-03-01)
We present the results of a four-month campaign searching for low-frequency radio transients near the North Celestial Pole with the Low-Frequency Array (LOFAR), as part of the Multifrequency Snapshot Sky Survey (MSSS). The ...
LOFAR, VLA, and Chandra observations of the Toothbrush galaxy cluster
(2016-02-22)
We present deep LOFAR observations between 120-181 MHz of the "Toothbrush" (RX J0603.3+4214), a cluster that contains one of the brightest radio relic sources known. Our LOFAR observations exploit a new and novel calibration ...
Spectral ageing in the lobes of cluster-centre FR II radio galaxies
(2015-12-21)
Recent investigations have shown that many parameters and assumptions made in the application of spectral-ageing models to FR II radio galaxies (e.g. injection index, uniform magnetic field, non-negligible cross-lobe age ...
Centaurus A: constraints on the nature of the giant lobe filaments from XMM-Newton observations
(2015-12-11)
We report on deep XMM-Newton observations of the vertex filament in the southern giant lobe of the Fanaroff-Riley class I radio galaxy Centaurus A. We find no X-ray excess from the filament region and place a 3 sigma upper ...
The link between accretion mode and environment in radio-loud active galaxies
(2015-11-01)
The interactions between radio-loud AGN and their environments play an important rôle in galaxy and cluster evolution. Recent work has demonstrated fundamental differences between high- and low-excitation radio galaxies ...
Disks and Jets : Gravity, Rotation and Magnetic Fields
(2015-10)
Magnetic fields are fundamental to the dynamics of both accretion disks and the jets that they often drive. We review the basic physics of these phenomena, the past and current efforts to model them numerically with an ...