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A Faraday rotation measure (RM) catalogue, or RM Grid, is a valuable resource for the study of cosmic magnetism. Using the second data release (DR2) from the LOFAR Two-metre Sky Survey (LoTSS), we have produced a catalogue of 2461…

We present a search for transient and highly variable sources at low radio frequencies (150-200 MHz) that explores long timescales of 1-3 years. We conducted this search by comparing the TIFR GMRT Sky Survey Alternative Data Release 1 (TGSS…

We present a 1.5deg x 8deg (220pc x 1195pc) Multiband Imaging Photometer for Spitzer 24um image of the Galactic Center and an accompanying point source list. This image is the highest spatial resolution (6" ~ 0.25pc) and sensitivity map…

Astrophysics · Physics 2009-11-13 J. L. Hinz , G. H. Rieke , F. Yusef-Zadeh , J. Hewitt , Z. Balog , M. Block

The CONT14 campaign with state-of-the-art VLBI data has observed the source 0642+449 with about one thousand observables each day during a continuous observing period of fifteen days, providing tens of thousands of closure delays---the sum…

Instrumentation and Methods for Astrophysics · Physics 2016-11-09 Ming H. Xu , Robert Heinkelmann , James M. Anderson , Julian Mora-Diaz , Harald Schuh , Guang L. Wang

With the Westerbork Synthesis Radio Telescope (WSRT), multi-frequency polarimetric images were taken of the diffuse radio synchrotron background in a region centered on (l,b) = (161,16). The observations were done simultaneously in 5…

Astrophysics · Physics 2011-05-23 Marijke Haverkorn , Peter Katgert , Ger de Bruyn

Using a recently completed survey of faint (sub-mJy) radio sources, selected at 1.4 GHz, a dust-free estimate of the local star formation rate (SFR) is carried out. The sample is 50% complete to 0.2 mJy, with over 50% of the radio sources…

Astrophysics · Physics 2009-10-31 B. Mobasher , L. Cram , A. Georgakakis , A. Hopkins

To explore the high frequency radio spectra of galaxies in clusters, we used NRAO's Very Large Array at four frequencies, 4.9-43 GHz, to observe 139 galaxies in low redshift (z<0.25), X-ray detected, clusters. The clusters were selected…

The 4.9 GHz Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey detected a drop in Interstellar Scintillation (ISS) for sources at redshifts z > 2, indicating an apparent increase in angular diameter or a decrease in flux…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-09 J. Y Koay , J. -P. Macquart , B. J. Rickett , H. E. Bignall , J. E. J. Lovell , C. Reynolds , D. L. Jauncey , T. Pursimo , L. Kedziora-Chudczer , R. Ojha

In this pilot investigation, precise optical positions in the FK5 system are presented for a set of 16 compact extragalactic radio sources, which will be part of the future radio--optical reference frame. The 0.9 m KPNO and CTIO telescopes…

Astrophysics · Physics 2009-10-28 N. Zacharias , C. de Vegt , L. Winter , K. J. Johnston

An extremely deep X-ray survey (about 1 Ms) of the Hubble Deep Field North and its environs (about 450 arcmin^2) has been performed with the Advanced CCD Imaging Spectrometer on board the Chandra X-ray Observatory. This is one of the two…

We conduct a stacking analysis using 1.4 GHz NRAO VLA Sky Survey (NVSS) detections and Planck all-sky maps to estimate the differential source counts down to the few 100 $\mu$Jy level at 30, 44, 70 and 100 GHz. Consequently, we are able to…

Astrophysics of Galaxies · Physics 2018-07-11 Eric J. Murphy , Ranga-Ram Chary

We present 6-GHz Very Large Array radio images of 70 gravitational lens systems at 300-mas resolution, in which the source is an optically-selected quasar, and nearly all of which have two lensed images. We find that about in half of the…

Astrophysics of Galaxies · Physics 2024-04-05 Neal Jackson , Shruti Badole , Thomas Dugdale , Hannah R. Stacey , Philippa Hartley , J. P. McKean , .

We present a low-frequency imaging study of an extended sample of X-shaped radio sources using the Giant Metrewave radio telescope (GMRT) at two frequencies (610 and 240 MHz). The sources were drawn from a Very Large Array FIRST-selected…

Astrophysics of Galaxies · Physics 2019-05-08 Dharam V. Lal , Biny Sebastian , C. C. Cheung , A. Pramesh Rao

This paper introduces a new Planck Catalog of Polarized and Variable Compact Sources (PCCS-PV) comprising 153 sources, the majority of which are extragalactic. The data include both the total flux density and linear polarization measured by…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-18 G. Rocha , R. Keskitalo , B. Partridge , A. Marscher , C. O'Dea , T. J. Pearson , K. M. Górski

We have measured the Faraday rotation of 62 extra-galactic background sources in 58 fields using the CSIRO Australia Telescope Compact Array (ATCA) with a frequency range of 1.1 - 3.1 GHz with 2048 channels. Our sources cover a region $\sim…

Astrophysics of Galaxies · Physics 2021-02-03 J. D. Livingston , N. M. McClure-Griffiths , B. M. Gaensler , A. Seta , M. J. Alger

I define 3 samples of extragalactic radio sources of type FRII, containing 26 objects in total. The control sample consists of 6C and 7C sources with radio-luminosities of around 10E27 W\Hz at 151 MHz and z~1. The other samples contain 3CRR…

Astrophysics · Physics 2009-09-29 Julie-Ann Goodlet

Precision geodesy relies on the stability of the International Celestial Reference Frame (ICRF), yet its reference sources, Active Galactic Nuclei (AGN), exhibit changes in source structure that can manifest as apparent shifts in their…

High Energy Astrophysical Phenomena · Physics 2026-05-20 Jeffrey A. Hodgson , Hana Krasna , Aletha de Witt , Pfesesani van Zyl , Janeth Valverde

This paper is part of a series describing the results from the Australia Telescope Hubble Deep Field South (ATHDFS) survey obtained with the Australia Telescope Compact Array (ATCA). This survey consists of observations at 1.4, 2.5, 5.2 and…

Astrophysics · Physics 2008-11-26 Minh T. Huynh , Carole A. Jackson , Ray P. Norris , Isabella Prandoni

We present a catalog of 110 variable stars within ~1' of Sgr A* based on image subtraction of near-infrared (H and K) photometry. Our images were obtained over 133 nights from 2000--2002 in H-band and over 134 nights from 2001--2002 in…

Astrophysics · Physics 2007-08-06 Molly S. Peeples , K. Z. Stanek , D. L. DePoy