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Related papers: New limits on extragalactic magnetic fields from r…

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To determine the properties of the Faraday screen and the magnetic field near the central region of the Galaxy, we measured the Faraday rotation measure (RM) towards 60 background extragalactic source components through the -6 deg < l <6…

Astrophysics · Physics 2009-11-13 Subhashis Roy , A. Pramesh Rao , Ravi Subrahmanyan

We discuss the magnetic field influence on diffuse gamma-ray emission from extragalactic electromagnetic cascades initiated by ultra-high energy cosmic rays. Regions in space vary considerably in field strength: it is possibly of 10^(-12) G…

High Energy Astrophysical Phenomena · Physics 2023-10-16 A. Uryson

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 construct a simple and robust approach for deriving constraints on magnetic fields in galaxy clusters from rotation measure (RM) maps. Relaxing the commonly used assumptions of a correlation between the magnetic field strength and the…

High Energy Astrophysical Phenomena · Physics 2013-09-19 Gilad Rave , Doron Kushnir , Eli Waxman

We present a study of the vertical magnetic field of the Milky Way towards the Galactic poles, determined from observations of Faraday rotation toward more than 1000 polarized extragalactic radio sources at Galactic latitudes |b| > 77 degs,…

We discuss the influence of extragalactic magnetic fields on the intensity of gamma-ray emission produced in electromagnetic cascades from ultra-high energy cosmic rays propagating in extragalactic space. Both cosmic rays and cascade…

High Energy Astrophysical Phenomena · Physics 2022-11-14 Anna Uryson

Observations of AGNs and microquasars by ASCA, RXTE, Chandra and XMM-Newton indicate the existence of wide X-ray emission lines of heavy ionized elements in their spectra. The emission can arise in the inner parts of accretion discs where…

Astrophysics · Physics 2009-11-07 A. F. Zakharov , N. S. Kardashev , V. N. Lukash , S. V. Repin

Understanding the role that magnetic fields play on the stage of galaxy formation requires accurate methods for inferring the properties of extragalactic magnetic fields. Radio synchrotron emission has been the most promising avenue to…

Astrophysics of Galaxies · Physics 2025-01-13 Tara Dacunha , Sergio Martin-Alvarez , Susan E. Clark , Enrique Lopez-Rodriguez

We examine the constraints imposed by Faraday rotation measures of extragalactic point sources on the structure of the magnetic field in the halo of our Galaxy. Guided by radio polarization observations of external spiral galaxies, we look…

Astrophysics of Galaxies · Physics 2017-03-29 Philippe Terral , Katia Ferriere

Rotation measure (RM) grids of extragalactic radio sources have been widely used for studying cosmic magnetism. But their potential for exploring the intergalactic magnetic field (IGMF) in filaments of galaxies is unclear, since other…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Takuya Akahori , B. M. Gaensler , Dongsu Ryu

Magnetic fields in elliptical galaxies are poorly constrained due to a lack of significant synchrotron emission from them. This paper explores properties of magnetic fields in ellipticals via two methods. First, we exploit the…

Astrophysics of Galaxies · Physics 2021-11-09 Hilay Shah , Amit Seta

Magnetic fields present in the Large Scale Structure (LSS) of the Universe change polarization of radio waves arriving from distant extragalactic sources through the effect of Faraday rotation. This effect has been recently used to detect…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-20 A. Neronov , F. Vazza , S. Mtchedlidze , E. Carretti

A variety of observations impose upper limits at the nano Gauss level on magnetic fields that are coherent on inter-galactic scales while blazar observations indicate a lower bound $\sim 10^{-16}$ Gauss. Such magnetic fields can play an…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-15 Tanmay Vachaspati

We present the review of various methods of detection of magnetic field strengths in the nearest regions of the active galaxy nuclei (AGN) which are the high energetic machines. Original spectropolarimetric method developed in the Pulkovo…

Astrophysics · Physics 2008-11-26 Yu. N. Gnedin , T. M. Natsvlishvili , M. Yu. Piotrovich

We made use of the two latest sets of Rotational Measures (RMs) of extra-galactic radio sources, namely the NRAO VLA Sky Survey otation Measures Catalogue, and a compilation by Kronberg&Newton-McGee(2011), to infer the global structure of…

Astrophysics of Galaxies · Physics 2015-05-27 M. S. Pshirkov , P. G. Tinyakov , P. P. Kronberg , K. J. Newton-McGee

We summarise the results found following a study of the effects that Galactic magnetic fields can have on the propagation of cosmic rays from local extragalactic sources. This study focuses on the coherent structures in the Jansson-Farrar…

High Energy Astrophysical Phenomena · Physics 2019-08-08 Andrew M. Taylor , A. M. Hillas

The large scale magnetic fields of our Galaxy have been mostly revealed by rotation measures ($RM$s) of pulsars and extragalactic radio sources. In the disk of our Galaxy, the average field strength over a few kpc scale is about 1.8 $\mu$G,…

Astrophysics · Physics 2009-10-31 J. L. Han

Magnetic fields in galaxies are produced via the amplification of seed magnetic fields of unknown nature. The seed fields, which might exist in their initial form in the intergalactic medium, were never detected. We report a lower bound…

High Energy Astrophysical Phenomena · Physics 2014-11-21 Andrii Neronov , Ievgen Vovk

We investigate the magnetic field in an intermediate-velocity filament for which the H$\alpha$ intensity in the WHAM survey correlates with excess Faraday rotation of extragalactic radio sources over the length of the filament from b ~ 20…

Astrophysics of Galaxies · Physics 2016-08-17 Jeroen M. Stil , Athena Hryhoriw

Results are presented of a new VLA-ROSAT study that probes the magnetic field strength and distribution over a sample of 16 ``normal'' low redshift (z < 0.1) galaxy clusters. The clusters span two orders of magnitude in X-ray luminosity,…

Astrophysics · Physics 2009-10-31 T. E. Clarke , P. P. Kronberg , H. Boehringer