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Related papers: On the amplification of magnetic fields in cosmic …

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We consider the possibility that cosmic magnetic field, instead of being uniformly distributed, is strongly correlated with the large scale structure of the universe. Then, the observed rotational measure of extra-galactic radio sources…

Astrophysics · Physics 2011-07-19 Dongsu Ryu , Hyesung Kang , Peter L. Biermann

Arguably the main challenge of galactic magnetism studies is to explain how the interstellar medium of galaxies reaches energetic equipartition despite the extremely weak cosmic primordial magnetic fields that are originally predicted to…

Astrophysics of Galaxies · Physics 2018-06-20 Sergio Martin-Alvarez , Julien Devriendt , Adrianne Slyz , Romain Teyssier

We study the amplification of magnetic fields during the formation of primordial halos. The turbulence generated by gravitational infall motions during the formation of the first stars and galaxies can amplify magnetic fields very…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jennifer Schober , Dominik Schleicher , Christoph Federrath , Simon Glover , Ralf Klessen , Robi Banerjee

Magnetic fields in galaxies and galaxy clusters are amplified from a very weak seed value to the observed $\mu{\rm G}$ strengths by the turbulent dynamo. The seed magnetic field can be of primordial or astrophysical origin. The strength and…

Astrophysics of Galaxies · Physics 2020-10-07 Amit Seta , Christoph Federrath

We discuss the amplification of magnetic fields by the small-scale dynamo, a process that could efficiently produce strong magnetic fields in the first galaxies. In addition, we derive constraints on the primordial field strength from the…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-14 Dominik R. G. Schleicher , Jennifer Schober , Christoph Federrath , Francesco Miniati , Robi Banerjee , Ralf S. Klessen

In this work we report a numerical study of the cosmic magnetic field amplification due to collisionless plasma instabilities. The collisionless magnetohydrodynamic equations derived account for the pressure anisotropy that leads, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 D. Falceta-Goncalves , G. Kowal

Magnetic fields play a vital role in numerous astrophysical processes such as star formation and the interstellar medium. In particular, their role in the formation and evolution of galaxies is not well understood. This paper presents…

Astrophysics of Galaxies · Physics 2021-12-10 Huai-Hsuan Chiu , Ke-Jung Chen

Magnetic fields play an important role in astrophysical accretion discs, and in the interstellar and intergalactic medium. They drive jets, suppress fragmentation in star-forming clouds and can have a significant impact on the accretion…

Plasma Physics · Physics 2016-12-30 Christoph Federrath

Observations of Faraday rotation and synchrotron emission in galaxy clusters imply large-scale magnetic fields with $\mu\mathrm{G}$ strengths possibly extending back to $z=4$. Non-radiative cosmological simulations of galaxy clusters show a…

In the present-day Universe, magnetic fields pervade galaxy clusters, with strengths of a few microGauss obtained from Faraday Rotation. Evidence for cluster magnetic fields is also provided by Megaparsec-scale radio emission, namely radio…

We study the amplification of large-scale magnetic fields during preheating and inflation in several different models. Preheating can resonantly amplify seed fields on cosmological scales. In the presence of conductivity, however, the…

Astrophysics · Physics 2009-10-31 Bruce A. Bassett , Giuseppe Pollifrone , Shinji Tsujikawa , Fermin Viniegra

The potential importance of magnetic fields during structure formation and gravitational collapse in the early Universe has been shown in several studies. In particular, magnetic field amplification by the small-scale dynamo plays an…

Astrophysics of Galaxies · Physics 2024-01-09 V. B. Díaz , D. R. G. Schleicher , M. A. Latif , P. Grete , R. Banerjee

Magnetic fields in galaxies are believed to be the result of dynamo amplification of initially weak seed fields, reaching equipartition strength inside the interstellar medium. The small-scale dynamo appears to be a viable mechanism to…

Astrophysics of Galaxies · Physics 2017-08-16 Michael Rieder , Romain Teyssier

We present the first study on the amplification of magnetic fields by the turbulent dynamo in the highly subsonic regime, with Mach numbers ranging from $10^{-3}$ to $0.4$. We find that for the lower Mach numbers the saturation efficiency…

High Energy Astrophysical Phenomena · Physics 2021-03-04 Radhika Achikanath Chirakkara , Christoph Federrath , Pranjal Trivedi , Robi Banerjee

We have performed magnetohydrodynamical simulations to study the amplification of magnetic fields in the precursors of shock waves. Strong magnetic fields are required in the precursors of the strong shocks that occur in supernova remnants.…

High Energy Astrophysical Phenomena · Physics 2015-06-17 M. Bruggen

Galactic cosmic rays are believed to be mostly accelerated at supernova shocks. However, the interstellar magnetic field is too weak to efficiently accelerate galactic cosmic rays up to the highest energies, i.e. $10^{15}$ eV. A stronger…

High Energy Astrophysical Phenomena · Physics 2016-03-16 Maria Victoria del Valle , Alexandre Lazarian , Reinaldo Santos-Lima

With ENZO simulations run on the J\"ulich supercomputers, we have investigated the evolution of magnetic fields in the largest cosmic structures (namely galaxy clusters and filaments connecting them) with unprecedented dynamical range.…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-26 Denis Wittor , Paola Domínguez-Fernández , Franco Vazza , Marcus Brüggen

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 nature and origin of turbulence and magnetic fields in the intergalactic space are important problems that are yet to be understood. We propose a scenario in which turbulent flow motions are induced via the cascade of the vorticity…

Astrophysics · Physics 2009-11-13 Dongsu Ryu , Hyesung Kang , Jungyeon Cho , Santabrata Das

Observations of non-thermal emission from several supernova remnants suggest that magnetic fields close to the blastwave are much stronger than would be naively expected from simple shock compression of the field permeating the interstellar…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Luke O'C. Drury , Turlough P. Downes