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Related papers: The First Magnetic Fields

200 papers

Magnetic fields play an important role at all stages of stellar evolution. In Sun-like stars, they are generated in the outer convective layers. Studying the large-scale magnetic fields of these stars enlightens our understanding of the…

Solar and Stellar Astrophysics · Physics 2015-06-17 R. Fares

Are magnetic fields important in primordial star formation? Assuming that star formation occurs via an accretion disk that is turbulent, initially because of local gravitational instability, we calculate the disk structure for realistic…

Astrophysics · Physics 2009-11-10 Jonathan C. Tan , Eric G. Blackman

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

Operating resonant mass detectors set interesting bounds on diffused backgrounds of gravitational radiation and in the next five years the wide-band interferometers will also look for stochastic sources. In this lecture the interplay among…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Massimo Giovannini

There is ample evidence for strong magnetic fields in the envelopes of (Post-)Asymptotic Giant Branch (AGB) stars as well as supergiant stars. The origin and role of these fields are still unclear. This paper updates the current status of…

Solar and Stellar Astrophysics · Physics 2019-03-14 Wouter Vlemmings

A new generation mechanism of the magnetic field in an inhomogeneous collisionless plasma with a beam component is proposed. We show that even though the current and charge neutralities are initially satisfied, the current neutrality is…

High Energy Astrophysical Phenomena · Physics 2020-06-17 Yutaka Ohira

Some common properties of helical magnetic fields in decaying and driven turbulence are discussed. These include mainly the inverse cascade that produces fields on progressively larger scales. Magnetic helicity also restricts the evolution…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

Despite their ubiquity, the origin of cosmic magnetic fields remains unknown. Various mechanisms have been proposed for their existence including primordial fields generated by inflation, or amplification and injection by compact…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 Harley Katz , Sergio Martin-Alvarez , Julien Devriendt , Adrianne Slyz , Taysun Kimm

In this letter, we discuss generation of magnetic field from cosmological perturbations. We consider the evolution of three component plasma (electron, proton and photon) evaluating the collision term between elecrons and photons up to the…

Astrophysics · Physics 2009-11-10 Keitaro Takahashi , Kiyotomo Ichiki , Hiroshi Ohno , Hidekazu Hanayama

In this letter we show that magnetic fields generated at the electroweak phase transition are most likely too weak to explain the void magnetic fields apparently observed today unless they have considerable helicity. We show that, in the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-15 Jacques M. Wagstaff , Robi Banerjee

There is strong observational evidence for the presence of large-scale magnetic fields MF in galaxies and clusters, with strength $\sim \mu$G and coherence lenght on the order of Kpc. However its origin remains as an outstanding problem.…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-08 Eduard F. Piratova , Edilson A. Reyes , Héctor J. Hortúa

Today, the generation of magnetic fields in solar-type stars and its relation to activity and rotation can coherently be explained, although it is certainly not understood in its entirety. Rotation facilitates the generation of magnetic…

Astrophysics · Physics 2009-11-13 A. Reiners , A. Scholz , J. Eislöffel , G. Hallinan , E. Berger , M. Browning , J. Irwin , M. Küker , S. Matt

Here we summarize our recent results of high-resolution computer simulations on the turbulent amplification of weak magnetic seed fields showing that such fields will be exponentially amplified also during the gravitational collapse…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-22 Robi Banerjee , Sharanya Sur , Christoph Federrath , Dominik R. G. Schleicher , Ralf S. Klessen

(abridged) A detailed examination of the evolution of stochastic magnetic fields between high cosmic temperatures and the present epoch is presented. A simple analytical model matching the results of the 3D MHD simulations allows for the…

Astrophysics · Physics 2009-11-10 Robi Banerjee , Karsten Jedamzik

Magnetic fields play an important role in producing and modifying the photospheric chemical peculiarities of intermediate-mass main sequence stars. This article discusses the basic theory and methods of measurement used to detect and…

Astrophysics · Physics 2007-05-23 G. A. Wade

Primordial magnetic fields may be created in collisions of expanding bubbles in a first-order cosmological phase transition and later serve as seed fields for galactic magnetic fields. Here I present results from numerical and analytical…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ola Tornkvist

Galaxy formation is at the heart of our understanding of cosmic evolution. Although there is a consensus that galaxies emerged from the expanding matter background by gravitational instability of primordial fluctuations, a number of…

Astrophysics of Galaxies · Physics 2020-06-10 Pratika Dayal , Andrea Ferrara

We study the possibility of generating magnetic fields during the evolution of electron, proton, and photon plasma in the pre-recombination era. We show that a small magnetic field can be generated in the second order of perturbation theory…

Astrophysics · Physics 2009-11-10 Rajesh Gopal , Shiv Sethi

We explore cosmological magnetogenesis in the post-inflationary universe, when the inflaton oscillates around its potential minimum and the universe is effectively dominated by cold matter. During this epoch prior to reheating, large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-29 Takeshi Kobayashi

The growing sample of magnetic stars shows a remarkable diversity in the properties of their magnetic fields. The overall goal of current studies is to understand the origin, evolution, and structure of stellar magnetic fields in stars of…

Solar and Stellar Astrophysics · Physics 2019-10-16 Swetlana Hubrig , Markus Schöller