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Related papers: Exploring weak magnetic fields with LOFAR and SKA

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Measurements of interplanetary magnetic fields have long relied on spacecraft measurements, which provide only in-situ sampling and therefore cannot capture the global magnetic structure. Faraday rotation of radio signals extends in-situ…

Space Physics · Physics 2026-05-28 Chuanpeng Hou , Huirong Yan , Siqi Zhao

The low-frequency linearly-polarised radio source population is largely unexplored. However, a renaissance in low-frequency polarimetry has been enabled by pathfinder and precursor instruments for the Square Kilometre Array. In this second…

Context. The existence of magnetic fields in the circumgalactic medium (CGM) is largely unconstrained. Their detection is important as magnetic fields can have a significant impact on the evolution of the CGM and, in turn, the fields can…

The structure of magnetic fields in galaxies remains poorly constrained, despite the importance of magnetism in the evolution of galaxies. Radio synchrotron and far-infrared (FIR) polarization and polarimetric observations are the best…

Unveiling the intergalactic magnetic field (IGMF) in filaments of galaxies is a very important and challenging subject in modern astronomy. In order to probe the IGMF from rotation measures (RMs) of extragalactic radio sources, we need to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Takuya Akahori , Kohei Kumazaki , Keitaro Takahashi , Dongsu Ryu

Magnetic fields remain an enigmatic part of the content of galaxy clusters. Faraday rotation and depolarisation of extragalactic radio sources are useful probes, but the limited availability of polarised radio sources necessitates stacking…

A VLA Sky Survey of the extragalactic sky at S band (2-4 GHz) with polarization information can uniquely probe the magneto-ionic medium in a wide range of astrophysical environments over cosmic time. For a shallow all-sky survey, we expect…

We describe a first attempt to derive properties of the regular and turbulent Galactic magnetic field from multi-frequency polarimetric observations of the diffuse Galactic synchrotron background. A single-cell-size model of the thin…

Astrophysics · Physics 2009-11-10 M. Haverkorn , P. Katgert , A. G. de Bruyn

Galaxy clusters are unique laboratories to investigate turbulent fluid motions and large scale magnetic fields. Synchrotron radio halos at the center of merging galaxy clusters provide the most spectacular and direct evidence of the…

Observing the magnetic fields of low-mass interacting galaxies tells us how they have evolved over cosmic time and their importance in galaxy evolution. We have measured the Faraday rotation of 80 extra-galactic radio sources behind the…

Astrophysics of Galaxies · Physics 2021-12-22 J. D. Livingston , N. M. McClure-Griffiths , S. A. Mao , Y. K. Ma , B. M. Gaensler , G. Heald , A. Seta

Aims - We report new Very Large Array polarimetric observations of Compact Steep-Spectrum (CSS) sources at 8.4, 15, and 23GHz. Methods - Using multi-frequency VLA observations we have derived sub-arcsecond resolution images of the total…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 F. Mantovani , A. Rossetti , W. Junor , D. J. Saikia , C. J. Salter

Wide-band radio polarization observations offer the possibility to recover information about the magnetic fields in synchrotron sources, such as details of their three-dimensional configuration, that has previously been inaccessible. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Cathy Horellou , Andrew Fletcher

We present a detailed depolarization analysis of the radio galaxy \texttt{ILTJ012215.21+254334.8} using polarimetric data from the \textit{LOFAR Two-metre Sky Survey} (LoTSS) Data Release 2 (DR2) catalogue. This source, with \textit{RM}…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-12 Samantha Sneha Paul , Abhik Ghosh

While the Low Frequency Array (LOFAR) is still in its commissioning phase, early science results are starting to emerge. Two nearby galaxies, M51 and NGC4631, have been observed as part of the Magnetism Key Science Project's (MKSP) effort…

We develop two algorithms, based on maximum likelihood (ML) inference, for estimating the parameters of polarized radio sources which emit at a single rotation measure (RM), e.g., pulsars. These algorithms incorporate the flux density…

Instrumentation and Methods for Astrophysics · Physics 2017-10-25 D. H. F. M. Schnitzeler , K. J. Lee

We study the challenges to detect the cosmic web at radio wavelengths with state-of-the-art cosmological simulations of extragalactic magnetic fields. The incoming generation of radio surveys operating at low frequency, like LOFAR, SKA-LOW…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-25 F. Vazza , M. Brueggen , C. Gheller , C. Ferrari , A. Bonafede

We investigate the potential of the Square Kilometre Array (SKA) for measuring the magnetic fields in clusters of galaxies via Faraday rotation of background polarised sources. [...] We find that about 10 per cent of the sky is covered by a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Martin Krause , Paul Alexander , Rosie Bolton , Joern Geisbuesch , David A. Green , Julia Riley

Calibration of instrumental polarization is critical for measuring polarized radio emissions from astrophysical sources to extract the magnetic field information in astrophysical, heliospheric, and terrestrial plasmas. At meter wavelengths,…

Instrumentation and Methods for Astrophysics · Physics 2025-05-08 Devojyoti Kansabanik , Angelos Vourlidas , Soham Dey , Surajit Mondal , Divya Oberoi

We present a study of the linear polarization properties of radio sources within the 10 deg$^2$ Wide Chandra Deep Field South (W-CDFS) in S-band (2-4 GHz). Our W-CDFS image has an angular resolution of 15 arcsec and a 1$\sigma$ RMS in…

We present a catalog of Faraday rotation measures (RMs) and redshifts for 4003 extragalactic radio sources detected at 1.4 GHz, derived by identifying optical counterparts and spectroscopic redshifts for linearly polarized radio sources…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-02 Alison M. Hammond , Timothy Robishaw , B. M. Gaensler