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No strong radio absorption detected in the low-frequency spectra of radio-loud quasars at z > 5.6
(2023-10-12)
We present the low-frequency radio spectra of 9 high-redshift quasars at $5.6 \leq z \leq 6.6$ using the Giant Metre Radio Telescope band-3, -4, and -5 observations ($\sim$300-1200 MHz), archival Low Frequency Array (LOFAR; ...
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 ...
The LOFAR Two-metre Sky Survey: the radio view of the cosmic star formation history
(2023-05-26)
We present a detailed study of the cosmic star formation history over $90$ per cent of cosmic time ($0\lesssim z\lesssim4$), using deep, radio continuum observations that probe star formation activity independent of dust. ...
The LOFAR Two-metre Sky Survey Deep Fields Data Release 1 V. Survey description, source classifications and host galaxy properties
(2023-04-29)
Source classifications, stellar masses and star formation rates are presented for 80,000 radio sources from the first data release of the Low Frequency Array Two-metre Sky Survey (LoTSS) Deep Fields, which represents the ...
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 ...
Extragalactic Peaked-Spectrum Radio Sources at Low-Frequencies are Young Radio Galaxies
(2022-12-20)
We present a sample of 373 peaked-spectrum (PS) sources with spectral peaks around 150 MHz, selected using a subset of the two LOw Frequency ARray (LOFAR) all-sky surveys, the LOFAR Two Meter Sky Survey and the LOFAR LBA ...
Cosmic evolution of low-excitation radio galaxies in the LOFAR Two-meter Sky Survey Deep Fields
(2022-04-26)
Feedback from low-excitation radio galaxies (LERGs) plays a key role in the lifecycle of massive galaxies in the local Universe; their evolution, and the impact of these active galactic nuclei on early galaxy evolution, ...
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 ...
Low-frequency radio spectra of submillimetre galaxies in the Lockman Hole
(2021-04-19)
We investigate the radio properties of a sample of 53 sources selected at 850 $\mu$m from the SCUBA-2 Cosmology Legacy Survey using new deep, low-frequency radio imaging of the Lockman Hole field from the Low Frequency ...