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Related papers: Exploring weak magnetic fields with LOFAR and SKA

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We present the results of the first survey and monitoring study of the linear polarisation properties of compact, flat-spectrum radio sources at millimetre/submillimetre wavelengths and discuss the implications of the inferred magnetic…

Astrophysics · Physics 2015-06-24 R. Nartallo , W. K. Gear , A. G. Murray , E. I Robson , J. H. Hough

Understanding origin and evolution of cosmological magnetic fields requires knowledge of magnetic fields in different extragalactic environments. In this context, a powerful tool is the statistical analysis of the Faraday effect on the…

We describe a recent full-polarization radio continuum survey, performed using the Westerbork Synthesis Radio Telescope (WSRT), of several nearby galaxies in the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample. The WSRT-SINGS survey…

Astrophysics of Galaxies · Physics 2009-11-23 G. Heald , R. Braun

Multi-frequency polarimetry with the Very Long Baseline Array (VLBA) telescope has revealed absolute Faraday Rotation Measures (RMs) in excess of 1000 rad/m/m in the central regions of 7 out of 8 strong quasars studied (e.g., 3C 273, 3C…

Astrophysics · Physics 2009-10-31 G. B. Taylor

The aim of this study is to probe the sub-mJy polarized source population with LOFAR. We present the method used to stack LOFAR polarization datasets, the resulting catalog of polarized sources, and the derived polarized source counts. The…

Faraday Rotation Measure (RM) Synthesis, as a method for analyzing multi-channel observations of polarized radio emission to investigate galactic magnetic fields structures, requires the definition of complex polarized intensity in the…

Astrophysics of Galaxies · Physics 2015-05-14 P. Frick , D. Sokoloff , R. Stepanov , R. Beck

It has been well established that galaxy clusters have magnetic fields. The exact properties and origin of these magnetic fields are still uncertain even though these fields play a key role in many astrophysical processes. Various attempts…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 E. Osinga , R. J. van Weeren , F. Andrade-Santos , L. Rudnick , A. Bonafede , T. Clarke , K. Duncan , S. Giacintucci , Tony Mroczkowski , H. J. A. Röttgering

The vast majority of extragalactic compact continuum radio sources are associated with star formation or jets from (super)massive black holes and, as such, are more likely to be found in association with starburst galaxies or early-type…

High Energy Astrophysical Phenomena · Physics 2023-12-20 D. Vohl , H. K. Vedantham , J. W. T. Hessels , C. G. Bassa , D. O. Cook , D. L. Kaplan , T. W. Shimwell , C. Zhang

GALFACTS is a large-area spectro-polarimetric survey on the Arecibo Radio telescope. It uses the seven-beam focal plane feed array receiver system (ALFA) to carry out an imaging survey project of the 12,700 square degrees of sky visible…

Instrumentation and Methods for Astrophysics · Physics 2011-11-22 Samuel J. George , Jeroen M. Stil , Mircea Andrecut , A. Russ Taylor

An understanding of cosmic magnetism requires converting the polarization properties of extragalactic radio sources into the rest-frame in which the corresponding polarized emission or Faraday rotation is produced. Motivated by this…

Astrophysics of Galaxies · Physics 2015-10-02 J. S. Farnes , B. M. Gaensler , E. Carretti

Low frequency radio waves, while challenging to observe, are a rich source of information about pulsars. The LOw Frequency ARray (LOFAR) is a new radio interferometer operating in the lowest 4 octaves of the ionospheric "radio window":…

Fast radio bursts (FRBs) are brief, intense flashes of radio waves from unidentified extragalactic sources. Polarized FRBs originate in highly magnetized environments. We report observations of the repeating FRB 20190520B spanning seventeen…

Low-frequency spectral studies of radio pulsars represent a key method for uncovering their emission mechanisms, magnetospheric structure, and signal interactions with the surrounding interstellar medium (ISM). In recent years, more…

Astrophysics of Galaxies · Physics 2025-10-13 Ting Yu , Zhongli Zhang , Hongyu Gong , Zhigang Wen

We investigate the possibility for the SKA to detect and study the magnetic fields in galaxy clusters and in the less dense environments surrounding them using Faraday Rotation Measures. To this end, we produce 3-dimensional magnetic field…

The goal of this work is to constrain the strength and structure of the magnetic field associated with the environment of the radio source 3C 449, using observations of Faraday rotation, which we model with a structure function technique…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 D. Guidetti , R. A. Laing , M. Murgia , F. Govoni , L. Gregorini , P. Parma

Millimeter wavelength polarimetry of accreting black hole systems can provide a tomographic probe of the accretion flow on a wide range of linear scales. We searched for linear polarization in two low luminosity active galactic nuclei…

High Energy Astrophysical Phenomena · Physics 2017-12-08 Geoffrey C. Bower , Jason Dexter , Sera Markoff , Ramprasad Rao , R. L. Plambeck

Faraday rotation measure at radio wavelengths is commonly used to diagnose large-scale magnetic fields. It is argued that the length-scales on which magnetic fields vary in large-scale diffuse astrophysical media can be inferred from…

High Energy Astrophysical Phenomena · Physics 2019-10-09 Alvina Y. L. On , Jennifer Y. H. Chan , Kinwah Wu , Curtis J. Saxton , Lidia van Driel-Gesztelyi

Predictions of the number of faint polarised radio sources that can be detected by SKA pathfinder telescopes and the SKA depend on the polarisation properties of radio sources with a total flux density around 1 mJy. Total intensity source…

Astrophysics · Physics 2009-06-23 J. M. Stil , A. R. Taylor , M. Krause , R. Beck

(Abridged) This paper introduces the formalism which connects between rotation measure ($\RM$) measurements for extragalactic sources and the cosmological magnetic field power spectrum. It is shown that the amplitude and shape of the…

Astrophysics · Physics 2016-08-30 Tsafrir Kolatt

We have studied the implications of high sensitivity polarization measurements of objects from the WMAP point source catalogue made using the VLA at 8.4, 22 and 43 GHz. The fractional polarization of sources is almost independent of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 R. A. Battye , I. W. A. Browne , M. W. Peel , N. J. Jackson , C. Dickinson
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