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Related papers: LBCS: the LOFAR Long-Baseline Calibrator Survey

200 papers

We present parameterized broadband spectral models valid at frequencies between 30-300 MHz for six bright radio sources selected from the 3C survey, spread in Right Ascension from 0-24 hours. For each source, data from the literature are…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Anna M. M. Scaife , George H. Heald

The LOw-Frequency ARray (LOFAR) is used to make precise measurements of radio emission from extensive air showers, yielding information about the primary cosmic ray. Interpreting the measured data requires an absolute and…

The Atacama Large millimeter/submillimeter Array (ALMA) obtains spatial resolutions of 15 to 5 milli-arcsecond (mas) at 275-950GHz (0.87-0.32mm) with 16km baselines. Calibration at higher-frequencies is challenging as ALMA sensitivity and…

We present the results of a survey of radio continuum sources near the Galactic plane using the Very Long Baseline Array (VLBA). Our observations are designed to identify compact extragalactic sources of milliarcsecond size that can be used…

Astrophysics of Galaxies · Physics 2015-05-27 K. Immer , A. Brunthaler , M. J. Reid , A. Bartkiewicz , Y. K. Choi , K. M. Menten , L. Moscadelli , A. Sanna , Y. W. Wu , Y. Xu , B. Zhang , X. W. Zheng

Aims. With the recent preliminary release of the LOFAR LBA Sky Survey (LoLSS), the first wide-area, ultra-low frequency observations from LOFAR were published. Our aim is to combine this data set with other surveys at higher frequencies to…

Instrumentation and Methods for Astrophysics · Physics 2023-06-22 Lukas Böhme , Dominik J. Schwarz , Francesco de Gasperin , Huub J. A. Röttgering , Wendy L. Williams

Context. Very Long Baseline Interferometry (VLBI) data are extremely sensitive to the phase stability of the VLBI array. This is especially important when we reach {\mu}Jy r.m.s. sensitivities. Calibration using standard phase referencing…

Instrumentation and Methods for Astrophysics · Physics 2016-02-24 Jack F. Radcliffe , Michael A. Garrett , Rob J. Beswick , Tom W. B. Muxlow , Peter Barthel , Adam T. Deller , Enno Middelberg

We present the first sub-mJy ($\approx0.7$ mJy beam$^{-1}$) survey to be completed below 100 MHz, which is over an order of magnitude deeper than previously achieved for widefield imaging of any field at these low frequencies. The high…

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

Context: New generation low-frequency telescopes are exploring a new parameter space in terms of depth and resolution. The data taken with these interferometers, for example with the LOw Frequency ARray (LOFAR), are often calibrated in a…

This paper presents the catalog of correlated flux densities in three ranges of baseline projection lengths of 637 sources from a 43 GHz (Q-band) survey observed with the Korean VLBI Network. Of them, 623 sources have not been observed…

Direction dependent calibration and imaging is a vital part of producing deep, high fidelity, high-dynamic range radio images with a wide-field low-frequency array like LOFAR. Currently, state-of-the-art facet-based direction dependent…

Instrumentation and Methods for Astrophysics · Physics 2020-03-25 J. G. Albert , R. J. van Weeren , H. T. Intema , H. J. A. Röttgering

We describe a method for spectral cleaning and timing calibration of short voltage time series data from individual radio interferometer receivers. It makes use of the phase differences in Fast Fourier Transform (FFT) spectra across antenna…

Instrumentation and Methods for Astrophysics · Physics 2016-05-04 A. Corstanje , S. Buitink , J. E. Enriquez , H. Falcke , J. R. Hörandel , M. Krause , A. Nelles , J. P. Rachen , P. Schellart , O. Scholten , S. ter Veen , S. Thoudam , T. N. G. Trinh

The ICARUS T600 LAr TPC is the far detector of the Short Baseline Program at FNAL. As it will have to work at shallow depth in the Booster Neutrino Beam, a large cosmic rays background ($\sim 11$ kHz) will be present. To reduce it, precise…

Instrumentation and Detectors · Physics 2020-06-24 M. Bonesini , R. Benocci , R. Bertoni , A. Falcone , R. Mazza , M. Torti , A. Menegolli , G. L. Raselli , M. Rossella

The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing sensitive, high-resolution 120-168MHz survey of the entire northern sky for which observations are now 20% complete. We present our first full-quality public data release. For this data…

Astrophysics of Galaxies · Physics 2018-11-21 T. W. Shimwell , C. Tasse , M. J. Hardcastle , A. P. Mechev , W. L. Williams , P. N. Best , H. J. A. Röttgering , J. R. Callingham , T. J. Dijkema , F. de Gasperin , D. N. Hoang , B. Hugo , M. Mirmont , J. B. R. Oonk , I. Prandoni , D. Rafferty , J. Sabater , O. Smirnov , R. J. van Weeren , G. J. White , M. Atemkeng , L. Bester , E. Bonnassieux , M. Brüggen , G. Brunetti , K. T. Chyży , R. Cochrane , J. E. Conway , J. H. Croston , A. Danezi , K. Duncan , M. Haverkorn , G. H. Heald , M. Iacobelli , H. T. Intema , N. Jackson , M. Jamrozy , M. J. Jarvis , R. Lakhoo , M. Mevius , G. K. Miley , L. Morabito , R. Morganti , D. Nisbet , E. Orrú , S. Perkins , R. F. Pizzo , C. Schrijvers , D. J. B. Smith , R. Vermeulen , M. W. Wise , L. Alegre , D. J. Bacon , I. M. van Bemmel , R. J. Beswick , A. Bonafede , A. Botteon , S. Bourke , M. Brienza , G. Calistro Rivera , R. Cassano , A. O. Clarke , C. J. Conselice , R. J. Dettmar , A. Drabent , C. Dumba , K. L. Emig , T. A. Enßlin , C. Ferrari , M. A. Garrett , R. T. Génova-Santos , A. Goyal , G. Gürkan , C. Hale , J. J. Harwood , V. Heesen , M. Hoeft , C. Horellou , C. Jackson , G. Kokotanekov , R. Kondapally , M. Kunert-Bajraszewska , V. Mahatma , E. K. Mahony , S. Mandal , J. P. McKean , A. Merloni , B. Mingo , A. Miskolczi , S. Mooney , B. Nikiel-Wroczyński , S. P. O'Sullivan , J. Quinn , W. Reich , C. Roskowiński , A. Rowlinson , F. Savini , A. Saxena , D. J. Schwarz , A. Shulevski , S. S. Sridhar , H. R. Stacey , S. Urquhart , M. H. D. van der Wiel , E. Varenius , B. Webster , A. Wilber

We present a detailed multi-epoch analysis of 31 potential southern hemisphere radio calibrators that were originally observed as part of a program to maintain the International Celestial Reference Frame (ICRF). At radio wavelengths, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 F. Hungwe , R. Ojha , R. S. Booth , M. F. Bietenholz , A. Collioud , P. Charlot , D. Boboltz , A. L. Fey

We carry out a shape and weak lensing analysis of Low Frequency Array (LOFAR) radio sources and Hyper Suprime-Cam (HSC) optical sources within the European Large Area Infrared Space Observatory Survey-North 1 (ELAIS-N1) field. Using HSC…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-27 Jinyi Liu , Reinout van Weeren , Huub Rottgering , Konrad Kuijken

Laser frequency combs (LFCs) are well on their way to becoming the next-generation calibration sources for precision astronomical spectroscopy. This development is considered key in the hunt for low-mass rocky exoplanets around solar-type…

We report on a recent 90 cm wide-field VLBI survey of two 3.1 deg^2 fields using the VLBA, Westerbork and Jodrell Bank telescopes. In-beam calibration was used to calibrate each field, the process was simplified by imaging the calibrators…

Astrophysics · Physics 2007-05-23 Emil Lenc , Mike A. Garrett , Olaf Wucknitz , James M. Anderson , Steven J. Tingay

We are pursuing a project to build a database of phase calibration sources suitable for Giant Metrewave Radio Telescope (GMRT). Here we present the first release of 45 low frequency calibration sources at 235 MHz and 610 MHz. These…

Instrumentation and Methods for Astrophysics · Physics 2016-10-19 Dharam V. Lal , Shilpa S. Dubal , Sachin S. Sherkar