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200 papers

The tearing mode instability is one important mechanism that may explain the triggering of fast magnetic reconnection in astrophysical plasmas such as the solar corona and the Earth's magnetosphere. In this paper, the linear stability…

Plasma Physics · Physics 2020-11-04 Chen Shi , Marco Velli , Fulvia Pucci , Anna Tenerani , Maria Elena Innocenti

Here we explore the role of temporal fluctuations in kinetic helicity on the generation of large-scale magnetic fields in presence of a background linear shear flow. Key techniques involved here are same as in our earlier work…

Fluid Dynamics · Physics 2021-10-13 Naveen Jingade , Nishant K. Singh

Aims: We quantify the effects of twisted magnetic fields on the development of the magnetic Kelvin-Helmholtz instability (KHI) in transversely oscillating coronal loops. Methods: We modelled a fundamental standing kink mode in a straight,…

Solar and Stellar Astrophysics · Physics 2017-11-22 Thomas Howson , Ineke De Moortel , Patrick Antolin

The most promising model for explaining the origin of solar magnetism is the flux transport dynamo model, in which the toroidal field is produced by differential rotation in the tachocline, the poloidal field is produced by the…

Solar and Stellar Astrophysics · Physics 2015-05-19 Arnab Rai Choudhuri

We show that the bulk transport magnetic current is generated by the moving magnetic kink crystal (chiral soliton lattice) formed in the chiral helimagnet under the static magnetic field applied perpendicular to the helical axis. The…

Strongly Correlated Electrons · Physics 2009-11-13 I. G. Bostrem , Jun-ichiro Kishine , A. S. Ovchinnikov

We show that when the electron and hole densities are unbalanced, observable nonlinear anomalous Hall effect and current-induced orbital magnetization appear at zero magnetic field in the weak charge ordering (CO) state of an organic…

Strongly Correlated Electrons · Physics 2020-10-21 Toshihito Osada , Andhika Kiswandhi

Extremely strong magnetic fields change the vacuum index of refraction. Although this polarization dependent effect is small for typical neutron stars, it is large enough to decouple the polarization states of photons traveling within the…

Astrophysics · Physics 2009-10-31 Jeremy S. Heyl , Nir J. Shaviv

Hydrodynamic and magnetohydrodynamic numerical studies of a mechanically forced two-vortex flow inside a sphere are reported. The simulations are performed in the intermediate regime between the laminar flow and developed turbulence where a…

Fluid Dynamics · Physics 2015-05-14 K. Reuter , F. Jenko , A. Tilgner , C. B. Forest

Using a rotating flat layer heated from below as an example, we consider effects which lead to stabilizing an exponentially growing magnetic field in magnetostrophic convection in transition from the kinematic dynamo to the full non-linear…

Fluid Dynamics · Physics 2015-05-18 P. Hejda , M. Reshetnyak

Large-scale magnetic fields in stars and galaxies are thought to arise by mean-field dynamo action due to the combined influence of both helical turbulence and shear. Those systems are also highly conducting and the turbulence therein leads…

Astrophysics of Galaxies · Physics 2019-05-22 Pallavi Bhat , Kandaswamy Subramanian , Axel Brandenburg

A convection-driven MHD dynamo in a rotating spherical shell, with clearly defined structural elements in the flow and magnetic field, is simulated numerically. Such dynamos can be called deterministic, in contrast to those explicitly…

Astrophysics · Physics 2008-11-26 A. V. Getling , R. D. Simitev , F. H. Busse

The inverse cascade of magnetic energy occurs when helicity or rotational instability exists in the magnetohydrodynamic (MHD) system. This well known phenomenon has been considered as a basis for the large scale magnetic field in universe.…

Plasma Physics · Physics 2016-02-16 Kiwan Park

The nonaxisymmetric 'kink-type' Tayler instability (TI) of toroidal magnetic fields is studied for conducting incompressible fluids of uniform density between two infinitely long cylinders rotating around the same axis. It is shown that for…

Solar and Stellar Astrophysics · Physics 2015-05-13 G. Ruediger , M. Schultz

For magnetic knots and links in plasmas we introduce an internal twist and study their dynamical behavior in numerical simulations. We use a set of helical and non-helical configurations and add an internal twist that cancels the helicity…

Solar and Stellar Astrophysics · Physics 2023-11-27 Simon Candelaresi , Celine Beck

Gravitational wave production induces a strong constraint on the amplitude of a primordial magnetic field. It has been shown that the nucleosynthesis bound for a stochastic gravitational wave background implies that causally generated…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Chiara Caprini , Ruth Durrer , Elisa Fenu

We analyze direct numerical simulations of large-scale dynamos in inhomogeneous nonhelically driven rotating turbulence with and without shear. The forcing is modulated so that the turbulent intensity peaks in the middle of the…

Plasma Physics · Physics 2025-05-02 Axel Brandenburg , Ethan T. Vishniac

We explore the possibility that matter bulk flows could generate the required vorticity in the electron-proton-photon plasma to source cosmic magnetic fields through the Harrison mechanism. We analyze the coupled set of perturbed Maxwell…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-05 J. A. R. Cembranos , A. L. Maroto , H. Villarrubia-Rojo

Tokamak disruptions are associated with breaking magnetic surfaces, which makes magnetic field lines chaotic in large regions of the plasma. The enforcement of quasi-neutrality in a region of chaotic field lines requires an electric…

Plasma Physics · Physics 2024-09-04 Allen H Boozer

A number of problems of solar and stellar dynamo theory are briefly reviewed and the current status of possible solutions is discussed. Results of direct numerical simulations are described in view of mean-field dynamo theory and the…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

We demonstrate theoretically and numerically the zonal-flow/drift-wave feedback mechanism for the LH transition in an idealised model of plasma turbulence driven by a small scale instability. Zonal flows are generated by a secondary…

Chaotic Dynamics · Physics 2010-12-17 Colm Connaughton , Sergey Nazarenko , Brenda Quinn