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Alignment in the orientation of LOFAR radio sources
(2020-08-25)
Various studies have laid claim to finding an alignment of the polarization vectors or radio jets of active galactic nuclei (AGN) over large distances, but these results have proven controversial and so far, there is no ...
The beautiful mess in Abell 2255
(2020-07-07)
We present LOFAR observations of one of the most spectacular objects in the radio sky: Abell 2255. This is a nearby ($z = 0.0806$) merging galaxy cluster hosting one of the first radio halos ever detected in the intra-cluster ...
The life cycle of radio galaxies in the LOFAR Lockman Hole field
(2020-06-08)
Radio galaxies are known to go through cycles of activity, where phases of apparent quiescence can be followed by repeated activity of the central supermassive black hole. A better understanding of this cycle is crucial ...
LOFAR first look at the giant radio galaxy 3C 236
(2019-07-28)
We have examined the giant radio galaxy 3C~236 using LOFAR at 143 MHz down to an angular resolution of 7", in combination with observations at higher frequencies. We have used the low frequency data to derive spectral index ...
LoTSS DR1 : Double-double radio galaxies in the HETDEX field
(2018-11-20)
Double-double radio galaxies (DDRGs) represent a short but unique phase in the life-cycle of some of the most powerful radio-loud active galactic nuclei (RLAGN). These galaxies display large-scale remnant radio plasma in ...
LoTSS/HETDEX: Disentangling star formation and AGN activity in gravitationally-lensed radio-quiet quasars
(2018-11-19)
Determining the star-forming properties of radio-quiet quasars is important for understanding the co-evolution of star formation and black hole accretion. Here, we present the detection of the gravitationally-lensed ...
LOFAR observations of the XMM-LSS field
(2018-11-19)
We present observations of the XMM Large-Scale Structure (XMM-LSS) field observed with the LOw Frequency ARray (LOFAR) at 120-168 MHz. Centred at a J2000 declination of $-4.5^{\circ}$, this is a challenging field to observe ...
The LOFAR Two-metre Sky Survey IV. First Data Release: Photometric redshifts and rest-frame magnitudes
(2018-11-19)
The LOFAR Two-metre Sky Survey (LoTSS) is a sensitive, high-resolution 120-168 MHz survey of the Northern sky. The LoTSS First Data Release (DR1) presents 424 square degrees of radio continuum observations over the HETDEX ...
The LoTSS view of radio AGN in the local Universe. The most massive galaxies are always switched on
(2018-11-15)
This paper presents a study of the local radio source population, by cross-comparing the data from the first data release (DR1) of the LOFAR Two-Metre Sky Survey (LoTSS) with the Sloan Digital Sky Survey (SDSS) DR7 main ...
The LOFAR Two-metre Sky Survey (LoTSS) III. First Data Release: optical/IR identifications and value-added catalogue
(2018-11-09)
The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing sensitive, high-resolution 120-168 MHz survey of the Northern sky with diverse and ambitious science goals. Many of the scientific objectives of LoTSS rely upon, or are ...