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Related papers: The LOFAR View of Cosmic Magnetism

200 papers

Bounds on the amplitude of a scale-invariant stochastic primordial magnetic field (PMF) can be significantly improved by measurements of the Faraday Rotation (FR) of CMB polarization. The mode-coupling correlations induced by FR make it…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 Levon Pogosian

We use the LOFAR Two-metre Sky Survey (LoTSS) Data Release I to identify the groups of galaxies (and individual galaxies) from the Hickson Compact Groups and Magnitude Limited Compact Groups samples that emit at the frequency of 150\,MHz,…

Magnetic fields in large scale structure filaments beyond galaxy clusters remain poorly understood. Superclusters offer a unique setting to study these low density environments, where weak signals make detection challenging. The Faraday…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-13 G. V. Pignataro , S. P. O'Sullivan , A. Bonafede , G. Bernardi , F. Vazza , E. Carretti

Low-frequency radio observations are revealing an increasing number of diffuse synchrotron sources from galaxy clusters, dominantly in the form of radio halos or radio relics. The existence of this diffuse synchrotron emission indicates the…

A primordial cosmological magnetic field induces Faraday rotation of the cosmic microwave background polarization. This rotation produces a curl-type polarization component even when the unrotated polarization possesses only gradient-type…

Astrophysics · Physics 2009-11-10 Arthur Kosowsky , Tina Kahniashvili , George Lavrelashvili , Bharat Ratra

Primordial magnetic fields (PMF) can create polarization $B$-modes in the cosmic microwave background (CMB) through Faraday rotation (FR), leading to non-trivial 2-point and 4-point correlators of the CMB temperature and polarization. We…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Amit P. S. Yadav , Levon Pogosian , Tanmay Vachaspati

The magnetic field of the solar wind near the Sun is very difficult to measure directly. Measurements of Faraday rotation of linearly polarized radio sources occulted by the solar wind provide a unique opportunity to estimate this magnetic…

Solar and Stellar Astrophysics · Physics 2015-06-04 X. P. You , W. A. Coles , G. B. Hobbs , R. N. Manchester

We search for observational signatures of magnetic helicity in data from all-sky radio polarization surveys of the Milky Way Galaxy. Such a detection would help confirm the dynamo origin of the field and may provide new observational…

Astrophysics of Galaxies · Physics 2020-10-14 J. L. West , R. N. Henriksen , K. Ferrière , A. Woodfinden , T. Jaffe , B. M. Gaensler , J. A. Irwin

Magnetic fields in galaxy clusters have been measured using a variety of techniques, including: studies of synchrotron relic and halo radio sources within clusters, studies of inverse Compton X-ray emission from clusters, surveys of Faraday…

Astrophysics · Physics 2009-11-07 C. L. Carilli , G. B. Taylor

The Universe's magnetogenesis can be investigated with radio observations of cosmic filaments, where the information on the initial magnetic field seeds is expected to be preserved in time. In this work, we update the comparison between…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-27 Ettore Carretti , Franco Vazza

High-energy cosmic rays, impinging on the atmosphere of the Earth initiate cascades of secondary particles, the extensive air showers. The electrons and positrons in the air shower emit electromagnetic radiation. This emission is detected…

High Energy Astrophysical Phenomena · Physics 2017-05-12 Jörg R. Hörandel , LOFAR key science project Cosmic Rays

Magnetic fields in nearby, star-forming galaxies reveal both large-scale patterns and small-scale structures. A large-scale field reversal may exist in the Milky Way but no such reversals have been observed so far in external galaxies. The…

Astrophysics of Galaxies · Physics 2015-05-30 David Moss , Rodion Stepanov , Tigran Arshakian , Rainer Beck , Marita Krause , Dmitri Sokoloff

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…

We present the first cosmological simulations of primordial magnetic fields derived from the constraints by the Cosmic Microwave Background observations, based on the fields' gravitational effect on cosmological perturbations. We evolved…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 F. Vazza , D. Paoletti , S. Banfi , F. Finelli , C. Gheller , S. O'Sullivan , M. Brüggen

Through polarization observations masers are unique probes of the magnetic field in a variety of different astronomical objects, with the different maser species tracing different physical conditions. In recent years maser polarization…

Astrophysics · Physics 2009-11-13 W. H. T. Vlemmings

Magnetic fields in the ionized medium of the disk and halo of the Milky Way impose Faraday rotation on linearly polarized radio emission. We compare two surveys mapping the Galactic Faraday rotation, one showing the rotation measures of…

In this invited talk, I first discuss the advantages and disadvantages of many probes for the magnetic fields of the Milky Way. I conclude that pulsars are the best probes for the magnetic structure in our Galaxy, because magnetic field…

Astrophysics of Galaxies · Physics 2013-08-06 JinLin Han

The measurement of magnetic fields in cosmic web filaments can be used to reveal the magnetogenesis of the Universe. In previous work, we produced first estimates of the field strength and its redshift evolution using the Faraday Rotation…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 E. Carretti , F. Vazza , S. P. O'Sullivan , V. Vacca , A. Bonafede , G. Heald , C. Horellou , S. Mtchedlidze , T. Vernstrom

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is the most sensitive radio telescope for pulsar observations. We make polarimetric measurements of a large number of faint and distant pulsars using the FAST. We present the…

Astrophysics of Galaxies · Physics 2022-12-01 Jun Xu , Jinlin Han , Pengfei Wang , Yi Yan

Magnetic fields are observed not only in stars, but in galaxies, clusters, and even high redshift Lyman-alpha systems. In principle, these fields could play an important role in structure formation and also affect the anisotropies in the…

Astrophysics · Physics 2009-10-31 Roy Maartens