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Related papers: The LOFAR View of Cosmic Magnetism

200 papers

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

Polarization measurements provide strong constraints on magnetic fields in star-forming systems. While magnetic field estimates of a few kiloGauss (kG) have been obtained near the surface of low-mass protostars, there are no analogous…

Astrophysics of Galaxies · Physics 2025-07-08 A. G. Cheriyan , S. Vig , Nirupam Roy , Samir Mandal , C. Carrasco-González , A. Rodríguez-Kamenetzky , A. Pasetto

The grand-design spiral galaxy M51 was observed with the LOFAR High Frequency Antennas (HBA) and imaged in total intensity and polarisation. This observation covered the frequencies between 115 MHz and 175 MHz. We produced an image of total…

Properties of planetary atmospheres, ionospheres, and magnetospheres are difficult to measure from Earth. Radio occultations are a common method for measuring these properties, but they traditionally rely on radio transmissions from a…

Earth and Planetary Astrophysics · Physics 2017-02-24 Paul Withers , Marissa F. Vogt

Observations of nearby star forming clouds with imaging X-ray telescopes have revealed that X-ray emission is elevated $10^1-10^4$ above main sequence levels in low-mass pre-main sequence (PMS) stars. The variability and spectral X-ray…

Astrophysics · Physics 2007-05-23 Eric D. Feigelson

Faraday rotation (RM) probes of magnetic fields in the universe are sensitive to cosmological and evolutionary effects as $z$ increases beyond $\sim $1 because of the scalings of electron density and magnetic fields, and the growth in the…

Astrophysics · Physics 2009-11-13 P. P. Kronberg , M. L. Bernet , F. Miniati , S. J. Lilly , M. B. Short , D. M. Higdon

The origin of extragalactic magnetic fields is still poorly understood. Based on a dedicated suite of cosmological magneto-hydrodynamical simulations with the ENZO code we have performed a survey of different models that may have caused…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 F. Vazza , M. Brüggen , C. Gheller , S. Hackstein , D. Wittor , P. M. Hinz

Understanding the physics of how stars form is a highly-prioritized goal of modern Astrophysics, in part because star formation is linked to both galactic dynamics on large scales and to the formation of planets on small scales. It is…

We present a broadband spectro-polarimetric analysis of 1,565 polarized radio sources from the LOFAR Two-Metre Sky Survey Data Release 2 (LoTSS-DR2) RM Grid catalogue. This study uses frequency-dependent Stokes Q and U spectra across the…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-20 Rudra Sinha , Abhik Ghosh

Fast radio bursts (FRBs) are observed to be highly polarized. Most have high linear polarization but a small fraction show significant circular polarization. We systematically investigate a variety of polarization mechanisms of FRBs within…

High Energy Astrophysical Phenomena · Physics 2023-04-19 Yuanhong Qu , Bing Zhang

This review concerns the origin and the possible effects of magnetic fields in the early Universe. We start by providing to the reader with a short overview of the current state of art of observations of cosmic magnetic fields. We then…

Astrophysics · Physics 2009-07-09 Dario Grasso , H. R. Rubinstein

We present LOFAR High-Band Array (HBA) observations of the Herschel-ATLAS North Galactic Pole survey area. The survey we have carried out, consisting of four pointings covering around 142 square degrees of sky in the frequency range…

We present a study of the magnetic field of the Large Magellanic Cloud (LMC), carried out using diffuse polarized synchrotron emission data at 1.4 GHz acquired at the Parkes Radio Telescope and the Australia Telescope Compact Array. The…

Magnetic fields play an important role in plasma dynamics, yet it is a quantity difficult to measure accurately with physical probes, whose presence disturbs the very field they measure. The Faraday rotation of a polarized beam of light…

The possibility of a polarization sounding of the pulsar magnetosphere is examined, using intrinsic pulsar emission as a probe signal, for modern radio telescopes operating in the meter and decameter wavelength range. Different models of…

Astrophysics of Galaxies · Physics 2015-06-11 O. M. Ulyanov , A. I. Shevtsova , A. A. Seredkina

We present the detection of 68 sources from the most sensitive radio survey in circular polarisation conducted to date. We use the second data release of the 144 MHz LOFAR Two-metre Sky Survey to produce circularly-polarised maps with…

A claimed detection of cosmological tensor perturbations from inflation via B-mode polarization of the cosmic microwave background requires distinguishing other possible B-mode sources. One such potential source of confusion is primordial…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Yilun Guan , Arthur Kosowsky

Magnetic fields in the Milky Way are present on a wide variety of sizes and strengths, influencing many processes in the Galactic ecosystem such as star formation, gas dynamics, jets, and evolution of supernova remnants or pulsar wind…

Measuring the magnetic field of the Milky Way reveals the structure and evolution of the galaxy. Pulsar rotation measures (RMs) provide a means to probe this Galactic magnetic field (GMF) in three dimensions. We use the largest…

Astrophysics of Galaxies · Physics 2025-04-17 L. S. Oswald , P. Weltevrede , B. Posselt , S. Johnston , A. Karastergiou , M. E. Lower

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":…