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Related papers: LOFAR low-band antenna observations of the 3C295 a…

200 papers

We present a catalogue of optical and near-infrared counterparts to radio sources detected in the Euclid Deep Field North (EDF-N) using observations from the LOw-Frequency ARray (LOFAR) High Band Antenna (HBA) at 144 MHz with 6 arcsec…

As a step toward investigating the parsec-scale properties of faint extragalactic radio sources, the Very Long Baseline Array (VLBA) was used at 5.0 GHz to obtain phase-referenced images of 76 sources in the NOAO Bootes field. These 76…

Astrophysics · Physics 2008-11-26 J. M. Wrobel , G. B. Taylor , T. A. Rector , S. T. Myers , C. D. Fassnacht

We present wide area, deep, high-resolution 153 MHz GMRT observations of the NOAO Bootes field, adding to the extensive, multi-wavelength data of this region. The observations, data reduction, and catalogue construction and description are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 W. L. Williams , H. T. Intema , H. J. A. Röttgering

We present LOFAR High-Band Array (HBA) observations of the Herschel-ATLAS North Galactic Pole survey area. The survey we have carried out, consisting of four pointings covering around 142 square degrees of sky in the frequency range…

We have obtained a deep radio image with the Very Large Array at 6 cm in the Lockman Hole. The noise level in the central part of the field is about 11 microJy. From these data we have extracted a catalogue of 63 radio sources. The analysis…

Astrophysics · Physics 2009-11-07 P. Ciliegi , G. Zamorani , G. Hasinger , I. Lehmann , G. P. Szokoly , G. Wilson

We present the first wide area (2.5 x 2.5 deg^2) LOFAR High Band Antenna image at a resolution of 1.2'' x 2'' with a median noise of approximately 80 microJy per beam. It was made from an 8-hour International LOFAR Telescope (ILT)…

This is the first of a series of papers based on sensitive 610 MHz observations of the ELAIS N1 field using the Giant Metrewave Radio Telescope. We describe the observations, processing and source catalogue extraction from a deep image with…

Astrophysics of Galaxies · Physics 2019-11-06 E. F. Ocran , A. R. Taylor , M. Vaccari , C. H. Ishwara-Chandra , I. Prandoni

The dominant source of radio continuum emissions at low frequencies is synchrotron radiation, which originates from star-forming regions in disk galaxies and from powerful jets produced by active galactic nuclei (AGN). We studied the Bootes…

Astrophysics of Galaxies · Physics 2023-08-22 Akriti Sinha , Abhirup Datta

It has been known for nearly three decades that high redshift radio galaxies exhibit steep radio spectra, and hence ultra-steep spectrum radio sources provide candidates for high-redshift radio galaxies. Nearly all radio galaxies with z > 3…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 C. H. Ishwara-Chandra , S. K. Sirothia , Y. Wadadekar , S. Pal , R. Windhorst

Low radio frequency surveys are important for testing unified models of radio-loud quasars and radio galaxies. Intrinsically similar sources that are randomly oriented on the sky will have different projected linear sizes. Measuring the…

The Low Frequency Array (LOFAR) is uniquely able to perform deep, 15" resolutions imaging at frequencies below 100 MHz. Observations in this regime, using the Low Band Antenna (LBA) system, are significantly affected by instrumental and…

Astrophysics of Galaxies · Physics 2026-01-14 J. M. Boxelaar , F. De Gasperin , M. J. Hardcastle , J. H. Croston , L. K. Morabito , R. J. van Weeren , H. Edler

(Abridged) This is the second in a series of three papers which present and interpret basic observational data on the 6C* 151-MHz radio sample: a low-frequency selected sample which exploits filtering criteria based on radio properties…

In our first paper we described three regions of the 9C survey of radio sources with the Ryle telescope at 15.2 GHz, constituting a total area of 520 deg^2 to a completeness limit of approximately 25 mJy. Here we report on a series of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 E. M. Waldram , G. G. Pooley , M. L. Davies , K. J. B. Grainge , P. F. Scott

We present the results from our deep (16x12 hour) Westerbork Synthesis Radio Telescope (WSRT) observations of the approximately 7 square degree Bootes Deep Field, centered at 14h32m05.75s, 34d16'47.5" (J2000). Our survey consists of 42…

We present preliminary results from the deepest VLBI observations yet conducted. VLBA+GBT 1.4 GHz observations of a region within NOAO-N, reach an r.m.s. noise level of 9 microJy per beam. Three sources are clearly detected (> 7 sigma)…

Astrophysics · Physics 2009-11-07 M. A. Garrett , J. M. Wrobel , R. Morganti

Relatively little information is available about the Universe at ultra-low radio frequencies, i.e. below 50 MHz (ULF), although the ULF spectral window contains a wealth of unique diagnostics for studying galactic and extragalactic…

We present a sample of 40 Ultra Steep Spectrum (USS, $\alpha \leq -1.3$, $S_{\nu}\propto \nu^{\alpha}$) radio sources selected from the Westerbork in the Southern Hemisphere (WISH) catalog. The USS sources have been imaged in K--band at the…

Ultra Steep Spectrum (USS) radio sources have been successfully used to select powerful radio sources at high redshifts (z>~2). Typically restricted to large-sky surveys and relatively bright radio flux densities, it has gradually become…

With the goal of investigating the nature and the environment of the faint radio sources (at mJy level), here are presented results of X-ray dentifications of Faint Imaging Radio Survey at Twenty centimetres (FIRST) in the 9 square degrees…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Khadija EL Bouchefry

LOFAR is the only radio telescope that is presently capable of high-sensitivity, high-resolution (<1 mJy/b and <15") observations at ultra-low frequencies (<100 MHz). To utilise these capabilities, the LOFAR Surveys Key Science Project is…