English
Related papers

Related papers: Magnetic fields in the first galaxies: Dynamo ampl…

200 papers

We study the cosmic evolution of the magnetic fields of a large sample of spiral galaxies in a cosmologically representative volume by employing a semi-analytic galaxy formation model and numerical dynamo solver in tandem. We start by…

Astrophysics of Galaxies · Physics 2019-01-03 Luiz Felippe S. Rodrigues , Luke Chamandy , Anvar Shukurov , Carlton M. Baugh , A. Russ Taylor

We show that the decaying magnetohydrodynamic turbulence leads to a more rapid growth of the correlation length of a primordial magnetic field than that caused by the expansion of the Universe. As an example, we consider the magnetic fields…

High Energy Physics - Phenomenology · Physics 2016-08-25 D. T. Son

Enormous progress has been made on observing stellar magnetism in stars from the main sequence through to compact objects. Recent data have thrown into sharper relief the vexed question of the origin of stellar magnetic fields, which…

Solar and Stellar Astrophysics · Physics 2015-06-24 Lilia Ferrario , Andrew Melatos , Jonathan Zrake

Magnetic fields are considered to be key components of massive stars, with a far-reaching impact on their evolution and ultimate fate. A magnetic mechanism was suggested for the collimated explosion of massive stars, relevant for…

Solar and Stellar Astrophysics · Physics 2024-10-28 Swetlana Hubrig , Markus Schöller , Silva P. Järvinen , Aleksandar Cikota , Michael Abdul-Masih , Ana Escorza , Ilya Ilyin

The origin of galactic and extra-galactic magnetic fields is an unsolved problem in modern cosmology. A possible scenario comes from the idea of these fields emerged from a small field, a seed, which was produced in the early universe…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-14 Hector J. Hortua , Leonardo Castaneda , Juan M. Tejeiro

We address the question of the existence of magnetic domains in a recent scenario for the creation of primordial magnetic fields. We write down the magnetohydrodynamic equation in an expanding universe in the infinite conductivity limit and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kari Enqvist , Poul Olesen

We consider the possibility of inflationary magnetogenesis due to dynamical couplings of the electromagnetic fields to gravity. We find that large primordial magnetic fields can be generated during inflation without the strong coupling…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-26 Peng Qian , Zong-Kuan Guo

The current understanding of astrophysical magnetic fields is reviewed, focusing on their generation and maintenance by turbulence. In the astrophysical context this generation is usually explained by a self-excited dynamo, which involves…

Astrophysics · Physics 2008-11-26 Axel Brandenburg , Kandaswamy Subramanian

Primordial magnetic fields (PMFs) generated in the early Universe may leave observable imprints in the present-day large-scale structure. However, it remains unclear on which spatial scales primordial signatures can survive the nonlinear…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-27 Jennifer Schober , Molly Abramson , Sayan Mandal , Salome Mtchedlidze , Tina Kahniashvili

We numerically investigate the generation of a magnetic field in a protostellar disc via an $\alpha \Omega$-dynamo and the resulting magnetohydrodynamic (MHD) driven outflows. We find that for small values of the dimensionless dynamo…

High Energy Astrophysical Phenomena · Physics 2018-03-05 Sergei Dyda , Richard V. E. Lovelace , Galina V. Ustyugova , Alexander V. Koldoba , Ira Wasserman

Small-scale turbulent dynamo is responsible for the amplification of magnetic fields on scales smaller than the driving scale of turbulence in diverse astrophysical media. Most earlier dynamo theories concern the kinematic regime and…

Astrophysics of Galaxies · Physics 2021-06-25 Siyao Xu , Alex Lazarian

Magnetic fields are one of most concealed components of the universe. They are observed as part of the intergalactic medium and on galaxy cluster scales, however their origin and evolution is unclear. In this work we use the IllustrisTNG…

Astrophysics of Galaxies · Physics 2023-05-04 Agustín M. Rodríguez-Medrano , Federico A. Stasyszyn , Dante J. Paz , Volker Springel

Massive stars are crucial building blocks of galaxies and the universe, as production sites of heavy elements and as stirring agents and energy providers through stellar winds and supernovae. The field of magnetic massive stars has seen…

Solar and Stellar Astrophysics · Physics 2015-05-27 Rolf Walder , Doris Folini , Georges Meynet

The early reionization of the intergalactic medium, which is favored from the WMAP temperature-polarization cross-correlations, contests the validity of the standard scenario of structure formation in the cold dark matter cosmogony. It is…

Astrophysics · Physics 2009-11-11 Hiroyuki Tashiro , Naoshi Sugiyama

Observations of dwarf galaxies suggest the presence of large-scale magnetic fields. However the size and slow rotation of these galaxies appear insufficient to support a mean-field dynamo action to excite such fields. Here we suggest a new…

Astrophysics of Galaxies · Physics 2017-02-08 David Moss , Dmitri Sokoloff

We discuss how gravitational waves could amplify seed magnetic fields to strengths capable of supporting the galactic dynamo. We consider the interaction of a weak magnetic field with gravity wave distortions in almost FRW cosmologies and…

Astrophysics · Physics 2014-10-13 C. G. Tsagas , P. K. S. Dunsby , M. Marklund

We reconstruct the 3D structure of magnetic fields, which were seeded by density perturbations during the radiation dominated epoch of the Universe and later on were evolved by structure formation. To achieve this goal, we rely on three…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-21 Sebastian Hutschenreuter , Sebastian Dorn , Jens Jasche , Franco Vazza , Daniela Paoletti , Guilhem Lavaux , Torsten A. Enßlin

We conduct a series of magnetohydrodynamical (MHD) simulations of magnetized interstellar medium (ISM) disturbed by exploding stars. Each star deposits a randomly oriented, dipolar magnetic field into ISM. The simulations are performed in a…

Astrophysics · Physics 2011-11-10 K. Kowalik , M. Hanasz

Detailed physical processes of magnetic field generation from density fluctuations in the pre-recombination era are studied. Solving Maxwell equations and the generalized Ohm's law, the evolutions of the net charge density, the electric…

Astrophysics · Physics 2008-11-26 Keitaro Takahashi , Kiyotomo Ichiki , Naoshi Sugiyama

A primordial magnetic field may be generated during an inflationary period if conformal invariance is broken. We reexamine and generalize previous results about the magnetic field produced by couplings of the form $R^n…

Astrophysics · Physics 2009-10-28 F. D. Mazzitelli , F. M. Spedalieri