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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; ...
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 ...
Sub-arcsecond imaging with the International LOFAR Telescope : I. Foundational calibration strategy and pipeline
(2022-02-28)
The International LOFAR Telescope is an interferometer with stations spread across Europe. With baselines of up to ∼2000 km, LOFAR has the unique capability of achieving sub-arcsecond resolution at frequencies below 200 ...
The LOFAR Two-metre Sky Survey -- V. Second data release
(2022-02-25)
In this data release from the ongoing LOw-Frequency ARray (LOFAR) Two-metre Sky Survey we present 120a 168 MHz images covering 27% of the northern sky. Our coverage is split into two regions centred at approximately 12h45m ...
Sub-arcsecond imaging with the International LOFAR Telescope. II. Completion of the LOFAR Long-Baseline Calibrator Survey
(2022-02-01)
The Low-Frequency Array (LOFAR) Long-Baseline Calibrator Survey (LBCS) was conducted between 2014 and 2019 in order to obtain a set of suitable calibrators for the LOFAR array. In this paper, we present the complete survey, ...
The LOFAR Two-metre Sky Survey: Deep Fields: : II. The ELAIS-N1 LOFAR deep field
(2021-04-07)
The LOFAR Two-metre Sky Survey (LoTSS) will cover the full northern sky and, additionally, aims to observe the LoTSS deep fields to a noise level of ~10 microJy/bm over several tens of square degrees in areas that have the ...
Low-frequency observations of the Giant Radio Galaxy NGC 6251
(2020-06-01)
We present LOFAR observations at 150 MHz of the borderline FRI/FRII giant radio galaxy NGC 6251. This paper presents the most sensitive and highest-resolution images of NGC 6251 at these frequencies to date, revealing for ...
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/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 ...
Radio-loud AGN in the first LoTSS data release: The lifetimes and environmental impact of jet-driven sources
(2018-11-19)
We constructed a sample of 23,344 radio-loud active galactic nuclei (RLAGN) from the catalogue derived from the LOFAR Two-Metre Sky Survey (LoTSS) survey of the HETDEX Spring field. Although separating AGN from star-forming ...