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Related papers: Magnetic Fields in Spiral Galaxies

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A framework is introduced for coupling the evolution of galactic magnetic fields sustained by the mean-field dynamo with the formation and evolution of galaxies in cold dark matter cosmology. Estimates of the steady-state strength of the…

Astrophysics of Galaxies · Physics 2015-05-20 Luiz Felippe S. Rodrigues , Anvar Shukurov , Andrew Fletcher , Carlton Baugh

Using the linearly polarized intensity and polarization angle data at 3.6, 6.2 and 20 cm, we determine variations of Faraday rotation and depolarization across the nearby galaxy M33. A 3-D model of the regular magnetic field is fitted to…

Astrophysics · Physics 2009-11-13 F. S. Tabatabaei , M. Krause , A. Fletcher , R. Beck

We seek the conditions for a {\it steady} mean field galactic dynamo. The parameter set is reduced to those appearing in the $\alpha^2$ and $\alpha/\omega$ dynamo, namely velocity amplitudes, and the ratio of sub-scale helicity to…

Astrophysics of Galaxies · Physics 2017-06-28 R. N. Henriksen

We present new Faraday rotation measures (RMs) for 148 extragalactic radio sources behind the southern Galactic plane (253o < l < 356o, |b| < 1.5o), and use these data in combination with published data to probe the large-scale structure of…

The usual theoretical model for synchrotron radiation in circular accelerators (synchrotrons and storage rings) is to treat a single electron moving in a horizontal circle in a uniform vertical magnetic field, but the true situation in real…

Accelerator Physics · Physics 2025-12-18 S. R. Mane

The presence of magnetic fields in the intra-cluster medium of galaxy clusters is now well estabilished. It is directly revealed by the presence of cluster-wide radio sources: radio halos and radio relics. In the last years increasing…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-08 A. Bonafede , L. Feretti , M. Murgia , F. Govoni , G. Giovannini , V. Vacca

We show that strong magnetic fields can be generated at shock waves associated with formation of galaxies or clusters of galaxies by the Weibel instability, an instability in collisionless plasmas. The estimated strength of the magnetic…

Astrophysics · Physics 2015-06-24 Yutaka Fujita , Tsunehiko N. Kato

The origin and growth of magnetic fields in galaxies is still something of an enigma. It is generally assumed that seed fields are amplified over time through the dynamo effect, but there are few constraints on the timescale. It has…

Studies of the three-dimensional (3D) structures of galactic magnetic fields are now entering a new era, with broadband, highly sensitive radio observations and new analysis methods. To reveal the magnetic field configuration from the…

Astrophysics of Galaxies · Physics 2023-03-07 Yuta Tashima , Takumi Ohmura , Mami Machida

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…

For over four decades, synchrotron-radiating sources have played a series of pathfinding roles in the study of galaxy clusters and large scale structure. Such sources are uniquely sensitive to the turbulence and shock structures of…

Large scale strong magnetic fields in galaxies are generally thought to have been generated by a mean field dynamo. In order to have generated the fields observed, the dynamo would have had to have operated for a sufficiently long period of…

Astrophysics · Physics 2007-05-23 A. Kandus , R. Opher , S. R. M. Barros

Magnetic fields are amplified as a consequence of galaxy formation and turbulence-driven dynamos. Galaxy mergers can potentially amplify the magnetic fields from their progenitors, making the magnetic fields dynamically important. However,…

Astrophysics of Galaxies · Physics 2021-04-05 Enrique Lopez-Rodriguez

We present a study of the magnetic field properties of NGC 4038/9 (the `Antennae' galaxies), the closest example of a late stage merger of two spiral galaxies. Wideband polarimetric observations were performed using the Karl G. Jansky Very…

Astrophysics of Galaxies · Physics 2016-09-21 Aritra Basu , S. A. Mao , Amanda A. Kepley , Timothy Robishaw , Ellen G. Zweibel , John. S. Gallagher

Galactic encounters are usually marked by a substantial increase of synchrotron emission of the interacting galaxies compared to the typical emission from similar isolated galaxies. This is believed to be associated with an increase of the…

Astrophysics of Galaxies · Physics 2014-07-02 David Moss , Dmitri Sokoloff , Rainer Beck , Marita Krause

Magnetic fields are observed beyond the peripheries of optically detected galactic discs, while numerical models of their origin and the typical magnitudes are still absent. Previously, studies of galactic dynamo have avoided considering…

Astrophysics of Galaxies · Physics 2014-09-05 E. Mikhailov , A. Kasparova , D. Moss , R. Beck , D. Sokoloff , A. Zasov

From our radio observations of the magnetic field strength and large-scale pattern of spiral galaxies of different Hubble types and star formation rates (SFR) we conclude that - though a high SFR in the disk increases the total magnetic…

Astrophysics of Galaxies · Physics 2009-11-13 Marita Krause

We propose a primordial-origin model for the composite configurations of global magnetic fields in spiral galaxies. We show that uniform tilted magnetic field wound up into a rotating disk galaxy can evolve into composite magnetic…

Astrophysics of Galaxies · Physics 2015-05-19 Yoshiaki Sofue , Mami Machida , Takahiro Kudoh

We investigate the cosmic ray driven dynamo in the interstellar medium of irregular galaxy. The observations (Chyzy et al. 2000, 2003) show that the magnetic field in irregular galaxies is present and its value reaches the same level as in…

High Energy Astrophysical Phenomena · Physics 2009-11-13 Hubert Siejkowski , Marian Soida , Katarzyna Otmianowska-Mazur , Michał Hanasz , Dominik Bomans

The extra stiffness that the magnetic field adds to the ISM changes the way it reacts to the presence of a spiral perturbation. At intermediate to high z, the gas shoots up before the arm, flows over, and falls behind it, as it approaches…

Astrophysics · Physics 2009-11-10 Gilberto C. Gomez , Donald P. Cox