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(abridged) The interpretation of Faraday rotation measure maps of AGNs within galaxy clusters has revealed regions, $\sim 50-100$ kpc, that are populated with large, $\sim 30 \mu$ G magnetic fields. The magnetic energy of these coherent…

Astrophysics · Physics 2009-10-31 S. A. Colgate , H. Li , V. Pariev

The origin and structure of the magnetic fields in the interstellar medium of spiral galaxies is investigated with 3D, non-ideal, compressible MHD simulations, including stratification in the galactic gravity field, differential rotation…

Astrophysics of Galaxies · Physics 2013-04-01 F. A. Gent , A. Shukurov , A. Fletcher , G. R. Sarson , M. J. Mantere

We discuss, using simple analytical models and MHD simulations, the origin and parameters of turbulence and magnetic fields in galaxy clusters. Three physically distinct regimes can be identified in the evolution of cluster turbulence and…

Astrophysics · Physics 2009-11-11 Kandaswamy Subramanian , Anvar Shukurov , Nils Erland L. Haugen

We present results of a detailed and fully non-linear numerical and analytical investigation of magnetic field evolution from the very earliest cosmic epochs to the present. We find that, under reasonable assumptions concerning the…

Astrophysics · Physics 2009-11-07 Robi Banerjee , Karsten Jedamzik

We propose a model of magnetic-field growth in galaxy clusters whereby the field is amplified by a factor of about 10^8 over a cosmologically short time of ~10^8 yr. Our model is based on the idea that the viscosity of the intracluster…

Astrophysics · Physics 2010-11-11 A. A. Schekochihin , S. C. Cowley

An important area of study of cosmic magnetic fields is on the largest scales, those of clusters of galaxies. In the last decade it has become clear that the intra-cluster medium (ICM) in clusters of galaxies is magnetized and that magnetic…

Astrophysics · Physics 2009-11-10 L. Feretti , M. Johnston-Hollitt

We search for magnetic fields outside galaxies and galaxy clusters by investigating redshift evolution of Faraday rotation measures (RM) of extragalactic radio sources. Our analysis reveals a strong evidence for the redshift dependence of…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-08 A. Neronov , D. Semikoz , M. Banafsheh

The origin of large-scale magnetic fields, detected in some low-mass (dwarf and irregular) galaxies via polarised synchrotron emission and Faraday rotation, remained unexplained for a long time. We suggest that mean-field dynamo can be…

Astrophysics of Galaxies · Physics 2019-10-16 Prasanta Bera , Anvar Shukurov , Kandaswamy Subramanian

The existence of microgauss magnetic fields in galaxy clusters have been established through observations of synchrotron radiation and Faraday rotation. They are conjectured to be generated via small-scale dynamo by turbulent flow motions…

High Energy Astrophysical Phenomena · Physics 2020-01-15 Soonyoung Roh , Dongsu Ryu , Hyesung Kang , Seungwoo Ha , Hanbyul Jang

The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms…

Astrophysics · Physics 2007-05-23 Kari Enqvist

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

Primordial magnetic fields (PMFs) are possible candidates for explaining the observed magnetic fields in galaxy clusters. Two competing scenarios of primordial magnetogenesis have been discussed in the literature: inflationary and…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-17 Salome Mtchedlidze , Paola Domínguez-Fernández , Xiaolong Du , Wolfram Schmidt , Axel Brandenburg , Jens Niemeyer , Tina Kahniashvili

The simulations of the formation of cosmological structure allows to determine the spatial inhomogeneity of cosmic magnetic fields. Such simulations, however, do not give an absolute number for the strength of the magnetic field due to…

Astrophysics · Physics 2007-05-23 Peter L. Biermann , Hyesung Kang , Joerg P. Rachen , Dongsu Ryu

Galaxies are observed to host magnetic fields with a typical total strength of around 15microgauss. A coherent large-scale field constitutes up to a few microgauss of the total, while the rest is built from strong magnetic fluctuations over…

Astrophysics of Galaxies · Physics 2024-01-09 Maarit J. Korpi-Lagg , Mordecai-Mark Mac Low , Frederick A. Gent

Observations of Faraday rotation through high-redshift galaxies have revealed that they host coherent magnetic fields that are of comparable strengths to those observed in nearby galaxies. These fields could be generated by fluctuation…

Astrophysics of Galaxies · Physics 2018-02-13 Sharanya Sur , Pallavi Bhat , Kandaswamy Subramanian

Additional physics beyond standard hydrodynamics is needed to fully model the intracluster medium (ICM); however, as we move to more sophisticated models, it is important to consider the role of magnetic fields and the way the fluid…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-04 Hilary Egan , Brian W. O'Shea , Eric Hallman , Jack Burns , Hao Xu , David Collins , Hui Li , Michael L. Norman

Future radio observations with the SKA and its precursors will be sensitive to trace spiral galaxies and their magnetic field configurations up to redshift $z\approx3$. We suggest an evolutionary model for the magnetic configuration in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 T. G. Arshakian , R. Stepanov , R. Beck , M. Krause , D. Sokoloff

We present a Bayesian maximum likelihood analysis of Faraday rotation measure (RM) maps of extended radio sources to determine magnetic field power spectra in clusters of galaxies. Using this approach, it is possible to determine the…

Astrophysics · Physics 2009-08-11 Corina Vogt , Torsten A. Ensslin

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

We present a study of the rotation measure (RM) obtained from a sample of extra-galactic radio sources either embedded in or seen in projection through a sample of seven southern galaxy clusters (declination less than 30 degrees). We…

Astrophysics · Physics 2007-05-23 M. Johnston-Hollitt , R. D. Ekers