English
Related papers

Related papers: Large-Scale Magnetic-Field Generation by Randomly …

200 papers

We investigate three-dimensional magnetohydrodynamics turbulence in the presence of both a large-scale velocity and non-uniform magnetic field. By assuming a turbulence driven by an external forcing with both helical and non-helical…

Fluid Dynamics · Physics 2015-05-13 Nicolas Leprovost , Eun-Jin Kim

Direct numerical simulations of two-dimensional decaying MHD turbulence in bounded domains show the rapid generation of angular momentum in nonaxisymmetric geometries. It is found that magnetic fluctuations enhance this mechanism. On a…

Plasma Physics · Physics 2010-09-02 Wouter J. T. Bos , Salah Neffaa , Kai Schneider

We study an example of instability in presence of a multiplicative noise, namely the spontaneous generation of a magnetic field in a turbulent medium. This so-called turbulent dynamo problem remains challenging, experimentally and…

Astrophysics · Physics 2016-08-16 Nicolas Leprovost , Bérengère Dubrulle

We start by pedagigically reviewing the problem of large scale magnetic fields. We explain the acquisition of angular momentum in the general context of Dark Matter models and we use this result to derive a dynamical mechanism for magnetic…

Astrophysics · Physics 2016-08-30 Hugues Sicotte

The influence of a magnetic field on the mass generation in 2+1 dimensional QED is considered.It is shown that the magnetic field is a catalyst of the generation of a fermion dynamical mass. The mass arises in the system with arbitrary…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. V. Shpagin

We consider possible geometries of magnetic fields in GRB outflows, and their evolution with distance from the source. For magnetically driven outflows, with an assumed ratio of magnetic to kinetic energy density of order unity, the field…

Astrophysics · Physics 2009-10-31 H. C. Spruit , F. Daigne , G. Drenkhahn

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

A weak fluctuating magnetic field embedded into a turbulent conducting medium grows exponentially while its characteristic scale decays. In the ISM and protogalactic plasmas, the magnetic Pr is very large, so a broad spectrum of growing…

Astrophysics · Physics 2008-11-26 Alexander Schekochihin , Steven Cowley , Jason Maron , Leonid Malyshkin

The Kelvin-Helmholtz (KH) instability of a shear layer with an initially-uniform magnetic field in the direction of flow is studied in the framework of 2D incompressible magnetohydrodynamics with finite resistivity and viscosity using…

Plasma Physics · Physics 2021-03-15 A. E. Fraser , P. W. Terry , E. G. Zweibel , M. J. Pueschel , J. M. Schroeder

We investigate numerically the long-time behavior of balanced Alfven wave turbulence forced at intermediate scales. Whereas the usual constant-flux solution is found at the smallest scales, two new scalings are obtained at the forcing…

Astrophysics · Physics 2007-10-25 S. Galtier , S. Nazarenko

We derive analytically the vorticity generated downstream of a two-dimensional rippled hydromagnetic shock neglecting fluid viscosity and resistivity. The growth of the turbulent component of the downstream magnetic field is driven by the…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Federico Fraschetti

We use high resolution direct numerical simulations (DNS) to show that helical turbulence can generate significant large-scale fields even in the presence of strong small-scale dynamo action. During the kinematic stage, the unified…

Astrophysics of Galaxies · Physics 2016-07-01 Pallavi Bhat , Kandaswamy Subramanian , Axel Brandenburg

We study the generation of strong large scale magnetic fields in dense quark matter. The magnetic field growth is owing to the magnetic field instability driven by the electroweak interaction of quarks. We discuss the situation when the…

High Energy Physics - Phenomenology · Physics 2016-11-16 Maxim Dvornikov

The origin and maintenance of coherent magnetic fields in the Universe is reviewed with an emphasis on the possible challenges that arise in their theoretical understanding. We begin with the interesting possibility that magnetic fields…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-12 Kandaswamy Subramanian

The explanation of the observed galactic magnetic fields may require the existence of a primordial magnetic field. Such a field may arise during the early cosmological phase transitions, or because of other particle physics related…

Astrophysics · Physics 2009-10-30 Kari Enqvist

We study the generation of large scale primordial magnetic fields by a cosmological phase transition during the radiation dominated era. The setting is a theory of N charged scalar fields coupled to an abelian gauge field, that undergoes a…

High Energy Physics - Phenomenology · Physics 2009-11-07 D. Boyanovsky , H. J. de Vega , M. Simionato

Understanding magnetic-field generation and amplification in turbulent plasma is essential to account for observations of magnetic fields in the universe. A theoretical framework attributing the origin and sustainment of these fields to the…

We present results from two-dimensional numerical simulations of a supersonic turbulent flow in the plane of the galactic disk, incorporating shear, thresholded and discrete star formation (SF), self-gravity, rotation and magnetic fields. A…

Astrophysics · Physics 2009-10-28 T. Passot , E. Vazquez-Semadeni , A. Pouquet

The presence of magnetic fields in many astrophysical objects is due to dynamo action, whereby a part of the kinetic energy is converted into magnetic energy. A turbulent dynamo that produces magnetic field structures on the same scale as…

Astrophysics of Galaxies · Physics 2020-03-19 Amit Seta , Paul J. Bushby , Anvar Shukurov , Toby S. Wood

We study the dynamical generation of masses for fundamental fermions in quenched quantum electrodynamics in the presence of weak magnetic fields using Schwinger-Dyson equations. Contrary to the case where the magnetic field is strong, in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alejandro Ayala , Adnan Bashir , Alfredo Raya , Eduardo Rojas
‹ Prev 1 8 9 10 Next ›