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Related papers: Exploring weak magnetic fields with LOFAR and SKA

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We have determined 194 Faraday rotation measures (RMs) of polarized extragalactic radio sources using new, multi-channel polarization observations at frequencies around 1.4 GHz from the Very Large Array (VLA) in the Galactic plane at…

Cosmological simulations predict that an intergalactic magnetic field (IGMF) pervades the large scale structure (LSS) of the Universe. Measuring the IGMF is important to determine its origin (i.e. primordial or otherwise). Using data from…

To study the strength and structure of the magnetic field in the Galactic centre (GC) we measured Faraday rotation of the radio emission of pulsars which are seen towards the GC. Three of these pulsars have the largest rotation measures…

Astrophysics of Galaxies · Physics 2016-04-20 D. H. F. M. Schnitzeler , R. P. Eatough , K. Ferrière , M. Kramer , K. J. Lee , A. Noutsos , R. M. Shannon

This chapter introduces the concepts of polarimetry in the case of low frequency radio astronomy. In this regime radio waves are usually not the signature of atomic or molecular transitions lines, but rather that of unstable particle…

Instrumentation and Methods for Astrophysics · Physics 2019-01-14 Baptiste Cecconi

Observational evidence for the existence of cosmic magnetic fields in intergalactic space coherent over Mpc scales is presented. Using an unprecedentedly large sample of Faraday rotation measures of radio sources from the NRAO VLA Sky…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-16 Jounghun Lee , Ue-Li Pen , A. Russell Taylor , Jeroen M. Stil , Caleb Sunstrum

Polarization from active galactic nuclei is interpreted as a signpost of the role of magnetic fields in the launch and collimation of their relativistic radio jets. Here, we report the detection of a clear polarization signal from ALMA…

Astrophysics of Galaxies · Physics 2018-12-26 I. Marti-Vidal , S. Muller

LOFAR, the "low-frequency array", will be one of the first in a new generation of radio telescopes and Square Kilometer Array (SKA) pathfinders that are highly flexible in capability because they are largely software driven. LOFAR will not…

Instrumentation and Methods for Astrophysics · Physics 2009-03-10 J. W. T. Hessels , B. W. Stappers , J. van Leeuwen , LOFAR Transients Key Science Project

Rotation Measure synthesis (RM synthesis) of the Westerbork Synthesis Radio Telescope (WSRT) observations at 2 m wavelength of the FAN region at l=137deg, b=+7deg shows the morphology of structures in the ionized interstellar medium. We…

Astrophysics of Galaxies · Physics 2015-06-11 Marco Iacobelli , Marijke Haverkorn , Peter Katgert

We present results of a wideband high-resolution polarization study of Hydra A, one of the most luminous FR I radio galaxies known and amongst the most well-studied. The radio emission from this source displays extremely large Faraday…

Astrophysics of Galaxies · Physics 2023-08-14 Lerato Baidoo , Richard A. Perley , Jean Eilek , Oleg Smirnov , Valentina Vacca , Torsten Ensslin

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…

This study evaluates the impact of Starlink satellites on low-frequency radio astronomy below 100 MHz, focusing on challenges on data processing and scientific goals. We conducted 40 hours of imaging observations using NenuFAR, in the…

The detection and study of magnetic fields surrounding galaxies is important to understand galaxy evolution since magnetic fields are tracers for dynamical processes in the circumgalactic medium (CGM) and can have a significant impact on…

We present high-resolution radio observations of a sample of 65 radio sources at low Galactic latitudes. The sources were all observed at 5 GHz with the Very Large Array A-array. MERLIN observations at 5 GHz of the ultracompact HII region…

Astrophysics · Physics 2009-11-10 D. J. Saikia , P. Thomasson , S. Roy , A. Pedlar , T. W. B. Muxlow

The presence of large-scale magnetic fields and ultra-relativistic electrons in the intra-cluster medium (ICM) is confirmed through the detection of diffuse radio synchrotron sources, so-called radio halos and relics. Due to their…

The role of magnetic fields in the dynamical evolution of galaxies and of the interstellar medium (ISM) is not well understood, mainly because such fields are difficult to directly observe. Radio astronomy provides the best tools to measure…

Astrophysics · Physics 2009-11-10 R. Beck , B. M. Gaensler

We present new polarisation observations at 13 cm, acquired using the Westerbork Synthesis Radio Telescope (WSRT), of 65 sources, from the B3-VLA sample of Compact Steep-Spectrum sources. These new data are combined with our VLA…

Astrophysics · Physics 2009-11-13 A. Rossetti , D. Dallacasa , C. Fanti , R. Fanti , K. -H. Mack

Faraday tomography is thought to be a powerful tool to explore cosmic magnetic field. Broadband radio polarimetric data is essential to ensure the quality of Faraday tomography, but such data is not easy to obtain because of radio frequency…

Instrumentation and Methods for Astrophysics · Physics 2018-12-05 Takuya Akahori , Shinsuke Ideguchi , Takahiro Aoki , Kazuhiro Takefuji , Hideki Ujihara , Keitaro Takahashi

The presence of magnetic fields in galaxy clusters has been well established in recent years, and their importance for the understanding of the physical processes at work in the Intra Cluster Medium has been recognized. Halo and relic…

Faraday rotation measures (RMs) of extragalactic radio sources provide information on line-of-sight magnetic fields, including contributions from our Galaxy, source environments, and the intergalactic medium (IGM). Looking at differences in…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-26 T. Vernstrom , B. Gaensler , L. Rudnick , H. Andernach

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…