English
Related papers

Related papers: Magnetic field generation by an inhomogeneous retu…

200 papers

The origin of the magnetic field in galaxies is an open question in astrophysics. Several mechanisms have been proposed related, in general, with the generation of small seed fields amplified by a dynamo mechanism. In general, these…

Astrophysics · Physics 2009-10-30 O. D. Miranda , M. Opher , R. Opher

We review current ideas on the origin of galactic and extragalactic magnetic fields. We begin by summarizing observations of magnetic fields at cosmological redshifts and on cosmological scales. These observations translate into constraints…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Lawrence M. Widrow , Dongsu Ryu , Dominik Schleicher , Kandaswamy Subramanian , Christos G. Tsagas , Rudolf A. Treumann

Miniati and Bell (2011) proposed a mechanism for the generation of magnetic seeds that is based the finite resistivity of the low temperature IGM in the high redshift universe. In this model, cosmic-ray protons generated by the first…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-20 Francesco Miniati , A. R. Bell

We investigate an efficient mechanism for generating magnetic fields in turbulent, collisionless plasmas. By using fully kinetic, particle-in-cell simulations of an initially non-magnetized plasma, we inspect the genesis of magnetization,…

Plasma Physics · Physics 2021-12-01 F. Pucci , M. Viviani , F. Valentini , G. Lapenta , W. H. Matthaeus , S. Servidio

If vector type perturbations are present in the primordial plasma before recombination, the generation of magnetic fields is known to be inevitable through the Harrison mechanism. In the context of the standard cosmological perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Shohei Saga , Kiyotomo Ichiki , Keitaro Takahashi , Naoshi Sugiyama

A variety of observations impose upper limits at the nano Gauss level on magnetic fields that are coherent on inter-galactic scales while blazar observations indicate a lower bound $\sim 10^{-16}$ Gauss. Such magnetic fields can play an…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-15 Tanmay Vachaspati

Experimental asymmetries in fusion implosions can lead to magnetic field generation in the hot plasma core. For typical parameters, previous studies found that the magnetisation Hall parameter, given by the product of the electron…

Plasma Physics · Physics 2021-03-17 James D. Sadler , Hui Li , Kirk A. Flippo

While plasma often behaves diamagnetically, we demonstrate that the laser irradiation of a thin opaque target with an embedded target-transverse seed magnetic field $B_\mathrm{seed}$ can trigger the generation of an order-of-magnitude…

A new magnetic field generation mechanism in electrostatic shocks is found, which can produce fields with magnetic energy density as high as 0.01 of the kinetic energy density of the flows on time scales $ \tilde \, 10^4 \,…

Plasma Physics · Physics 2015-06-22 A. Stockem , T. Grismayer , R. A. Fonseca , L. O. Silva

A strong electron current triggered by a femtosecond relativistically intense laser pulse in a foil coil-like target is shown to be able to generate a solenoidal-type extremely strong magnetic field. The magnetic field lifetime sufficiently…

Plasma Physics · Physics 2019-05-21 A. V. Brantov , Ph. Korneev , V. Yu. Bychenkov

The Kelvin-Helmholtz instability in an ionized plasma is considered with a focus on the generation of magnetic field via the Biermann battery mechanisms. The problem is studied through direct numerical simulations of two counter-directed…

Plasma Physics · Physics 2014-08-11 Mikhail Modestov , Vitaly Bychkov , Gert Brodin , Mattias Marklund , Axel Brandenburg

Anisotropy of kinetic coefficients in presence of a magnetic field is represented by Hall currents, which appear in a collisional medium due to action of the Lorentz force on the charged particles between collisions. We derive equations,…

Plasma Physics · Physics 2026-04-28 G. S. Bisnovatyi-Kogan , M. V. Glushikhina

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

Astrophysics · Physics 2009-11-13 Yutaka Fujita , Tsunehiko N. Kato

Magnetic fields appear to be present in all galaxies and galaxy clusters. Recent measurements indicate that a weak magnetic field may be present even in the smooth low density intergalactic medium. One explanation for these observations is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Smadar Naoz , Ramesh Narayan

A rigorous theory for the generation of a large-scale magnetic field by random non-helically forced motions of a conducting fluid combined with a linear shear is presented in the analytically tractable limit of low Rm and weak shear. The…

Astrophysics · Physics 2011-12-15 T. Heinemann , J. C. McWilliams , A. A. Schekochihin

We present the results of 3-dimensional kinetic simulations and theoretical studies on the formation and evolution of the current sheet in a collisionless plasma during magnetic field annihilation in the ultra-relativistic limit.…

Plasma Physics · Physics 2019-12-20 Y. J. Gu , F. Pegoraro , P. V. Sasorov , D. Golovin , A. Yogo , G. Korn , S. V. Bulanov

It is demonstrated that targets with a broken rotational symmetry may facilitate generation of a strong axial (poloidal) magnetic field. An intense laser beam irradiating such a target creates intense electron currents carrying vorticity…

Plasma Physics · Physics 2017-04-05 Ph. Korneev , V. Tikhonchuk , E. d'Humières

We propose a new mechanism for turbulent mean-field dynamo in which the magnetic fluctuations resulting from a small-scale dynamo drive the generation of large-scale magnetic fields. This is in stark contrast to the common idea that…

Solar and Stellar Astrophysics · Physics 2015-11-23 Jonathan Squire , Amitava Bhattacharjee

We investigate numerically magnetic field generation by thermal convection with square periodicity cells in a rotating horizontal layer of electrically-conducting fluid with stress-free electrically perfectly conducting boundaries for…

Chaotic Dynamics · Physics 2010-04-12 V. Zheligovsky

We demonstrate by computer simulations, laser plasma experiments, and analytic theory that a hitherto unknown instability is excited in the beam plasma system with finite transverse size. This instability is responsible for the generation…