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

200 papers

With the continuous advancement of laser technology, accurately evaluating the noise spectrum of high-performance lasers has become increasingly challenging. In this work, we demonstrate a high-precision laser spectrum analyzer based on the…

Optics · Physics 2025-05-28 Zhongwang Pang , Chunyi Li , Hongfei Dai , Wenlin Li , Dongqi Song , Fei Meng , Yige Lin , Bo Wang

Optical frequency comb synthesizers (FCs) [1] are laser sources covering a broad spectral range with a number of discrete, equally spaced and highly coherent frequency components, fully controlled through only two parameters: the frequency…

We conducted a follow-up study on the analysis of the LOw Frequency ARray (LOFAR) Two-metre Sky Survey (LoTSS) mosaic in the high-latitude outer Galaxy presented in the first paper of this series. Here, we focus on the search for alignment…

Astrophysics of Galaxies · Physics 2024-07-10 Ana Erceg , Vibor Jelić , Marijke Haverkorn , Andrea Bracco , Lana Ceraj , Luka Turić , Juan D. Soler

Low-cost particulate matter sensors (LCS) are an important source of air quality data, improving the spatial and temporal resolution of data gathered by sparsely placed official monitoring stations. Their readings, however, are subject to…

Atmospheric and Oceanic Physics · Physics 2024-03-15 Robert Blaga

Atmospheric propagation effects at millimeter wavelengths can significantly alter the phases of radio signals and reduce the coherence time, putting tight constraints on high frequency Very Long Baseline Interferometry (VLBI) observations.…

The new generation of high-resolution broad-band radio telescopes, like the Low Frequency Array (LOFAR), produces, depending on the level of compression, between 1 to 10 TB of data per hour after correlation. Such a large amount of…

Instrumentation and Methods for Astrophysics · Physics 2019-11-12 A. Drabent , M. Hoeft , A. P. Mechev , J. B. R. Oonk , T. W. Shimwell , F. Sweijen , A. Danezi , C. Schrijvers , C. Manzano , O. Tsigenov , R. -J. Dettmar , M. Brüggen , D. J. Schwarz

The Blanco Cosmology Survey (BCS) is a 60 night imaging survey of $\sim$80 deg$^2$ of the southern sky located in two fields: ($\alpha$,$\delta$)= (5 hr, $-55^{\circ}$) and (23 hr, $-55^{\circ}$). The survey was carried out between 2005 and…

This paper provides an overview of the PACS photometer flux calibration concept, in particular for the principal observation mode, the scan map. The absolute flux calibration is tied to the photospheric models of five fiducial stellar…

(Context.) A number of millimeter and submillimeter facilities with linear polarization observing capabilities have started operating during last years. These facilities, as well as other previous millimeter telescopes and interferometers,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Ivan Agudo , Clemens Thum , Helmut Wiesemeyer , Sol N. Molina , Carolina Casadio , Jose L. Gomez , Dimitrios Emmanoulopoulos

We present Low-Frequency Array (LOFAR) telescope observations of the radio-loud gravitational lens systems MG 0751+2716 and CLASS B1600+434. These observations produce images at 300 milliarcseconds (mas) resolution at 150 MHz. In the case…

Interferometric calibration always yields non unique solutions. It is therefore essential to remove these ambiguities before the solutions could be used in any further modeling of the sky, the instrument or propagation effects such as the…

Instrumentation and Methods for Astrophysics · Physics 2013-07-19 Sarod Yatawatta

The ambitious scientific goals of SKA require a matching capability for calibration of instrumental and atmospheric propagation contributions as functions of time, frequency and position. The development of novel calibration algorithms to…

Instrumentation and Methods for Astrophysics · Physics 2022-02-01 María J. Rioja , Richard Dodson

A catalog containing milliarcsecond--accurate positions of 1332 extragalactic radio sources distributed over the northern sky is presented - the Very Long Baseline Array Calibrator Survey (VCS1). The positions have been derived from…

Astrophysics · Physics 2010-04-06 A. J. Beasley , D. Gordon , A. B. Peck , L. Petrov , D. S. MacMillan , E. B. Fomalont , C. Ma

We present a study of the low-frequency radio properties of broad absorption line quasars (BALQSOs) from the LOFAR Two-metre Sky-Survey Data Release 1 (LDR1). The value-added LDR1 catalogue contains Pan-STARRS counterparts, which we match…

Published analyses of very long baseline interferometry (VLBI) data for the sources included in the third International Celestial Reference Frame (ICRF3) catalog have revealed object-specific, excess astrometric variability and…

Astrophysics of Galaxies · Physics 2024-11-27 Valeri V. Makarov , Phil Cigan , David Gordon , Megan C. Johnson , Christopher DiLullo , Sébastien Lambert

This work concerns the development of a 3D measuring system able to realize noncontact surface topography with millimetric depth-range and micrometric resolutions both in the spatial and depth axes. The optical concept is based on the well…

Instrumentation and Detectors · Physics 2018-08-24 C. Pernechele , S. Chinellato , F. Manzan , S. Carmignato , A. Voltan

We present the first results from our survey of intervening and proximate Lyman limit systems (LLSs) at $z$$\sim$2.0-2.5 using the Wide Field Camera 3 on-board the Hubble Space Telescope. The quasars in our sample are projected pairs with…

Aims: We computed a celestial reference frame (CRF) from Very Long Baseline Interferometry (VLBI) Global Observing System (VGOS) data after five years of regular observations (155 multi-baseline 24-hour VGOS sessions until 2024.0). In this…

Instrumentation and Methods for Astrophysics · Physics 2024-11-25 Hana Krasna , Christopher S. Jacobs , Matthias Schartner , Patrick Charlot

High-frequency long-baseline experiments with the Atacama Large Millimeter/submillimeter Array were organized to test the high angular resolution imaging capabilities in the submillimeter wave regime using baselines up to 16 km. Four…

Detections of the cross correlation signal between the 21cm signal during reionization and high-redshift Lyman Alpha emitters (LAEs) are subject to observational uncertainties which mainly include systematics associated with radio…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 Anne Hutter , Cathryn M. Trott , Pratika Dayal