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The LOFAR Two-Metre Sky Survey : VI. Optical identifications for the second data release
(2023-10-01)
The second data release of the LOFAR Two-Metre Sky Survey (LoTSS) covers 27% of the northern sky, with a total area of ∼5700 deg1. The high angular resolution of LOFAR with Dutch baselines (6 arcsec) allows us to carry out ...
Discovery of 24 radio-bright quasars at $4.9 \leq z \leq6.6$ using low-frequency radio observations
(2022-12-31)
High redshift quasars ($z>5$) that also shine brightly at radio wavelengths are unique signposts of supermassive black hole activity in the early universe. However, bright radio sources at $z\ge5$ are extremely rare and ...
Accretion mode versus radio morphology in the LOFAR Deep Fields
(2022-02-16)
Radio-loud active galaxies have two accretion modes [radiatively inefficient (RI) and radiatively efficient (RE)], with distinct optical and infrared signatures, and two jet dynamical behaviours, which in arcsec- to ...
Low frequency radio properties of the $z>5$ quasar population
(2021-12-31)
Optically luminous quasars at z > 5 are important probes of super-massive black hole (SMBH) formation. With new and future radio facilities, the discovery of the brightest low-frequency radio sources in this epoch would ...
The LOFAR Two Metre Sky Survey: Deep Fields Data Release 1. III. Host-galaxy identifications and value added catalogues
(2021-04-07)
We present the source associations, cross-identifications, and multi-wavelength properties of the faint radio source population detected in the deep tier of the LOFAR Two Metre Sky Survey (LoTSS): the LoTSS Deep Fields. ...
The LOFAR Two-metre Sky Survey Deep Fields: Data release 1. IV. Photometric redshifts and stellar masses
(2021-04-07)
The Low Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS) is a sensitive, high-resolution 120-168 MHz survey split across multiple tiers over the northern sky. The first LoTSS Deep Fields data release consists of deep ...
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 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 ...
Giant radio galaxies in the LOFAR Two-metre Sky Survey-I
(2020-03-01)
Giant radio galaxies (GRGs) are a subclass of radio galaxies which have grown to megaparsec scales. GRGs are much rarer than normal sized radio galaxies ( less than 0.7 Mpc) and the reason for their gigantic sizes is still ...
A LOFAR-IRAS cross-match study : the far-infrared radio correlation and the 150-MHz luminosity as a star-formation rate
(2019-11-01)
Aims. We aim to study the far-infrared radio correlation (FIRC) at 150 MHz in the local Universe (at a median redshift z~0:05) and improve the use of the rest-frame 150-MHz luminosity, L150, as a star-formation rate (SFR) ...