Related papers: Current sheet formation and non-ideal behaviour at…
The strong magnetic field of neutron stars is intimately coupled to the observed temperature and spectral properties, as well as to the observed timing properties (distribution of spin periods and period derivatives). Thus, a proper…
Instabilities in relativistic magnetized jets are thought to be deeply connected to their energy dissipation properties and to the consequent acceleration of the non-thermal emitting relativistic particles. Instabilities lead to the…
In this paper, we investigate a simple model where two, initially unconnected, flux systems are forced to interact in response to the imposed boundary driving by solving the non-ideal 3D MHD equations numerically. The reconnection rate of…
The dynamics of a plasmoid chain is studied with three dimensional Particle-in-Cell simulations. The evolution of the system with and without a uniform guide field, whose strength is 1/3 the asymptotic magnetic field, is investigated. The…
We present the results of a set of three-dimensional numerical simulations of magnetic flux emergence from below the photosphere into the corona that include a uniform and horizontal coronal magnetic field mimicking a pre-existing…
Numerical simulations of strongly compressible MHD corresponding to a stellar atmosphere with substantial gravity and near force-free magnetic fields show that the current sheet collapses (its width decreasing substantially). As a result,…
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…
Numerical evidence for a finite-time singularity in ideal 3D magnetohydrodynamics (MHD) is presented. The simulations start from two interlocking magnetic flux rings with no initial velocity. The magnetic curvature force causes the flux…
Recent advances in theory and computational experiments have shown the need to refine the previous categorisation of magnetic reconnection at three-dimensional null points -- points at which the magnetic field vanishes. We propose here a…
High-energy astrophysical systems and compact objects are frequently modeled using ideal relativistic magnetohydrodynamic (MHD) or force-free electrodynamic (FFE) simulations, with the underlying assumption that the discretisation from the…
We provide compelling numerical evidence for the development of (potential) finite-time singularities in the three-dimensional (3D) axisymmetric, ideal, incompressible magnetohydrodynamic (IMHD) equations, in a wall-bounded cylindrical…
Kinetic simulations have demonstrated that three-dimensional reconnection in collisionless regimes proceeds through the formation and interaction of magnetic flux ropes, which are generated due to the growth of tearing instabilities at…
We present new simulations of the evolution of axially symmetric magnetic fields in neutron star crusts under the influence of the Hall effect and subdominant Ohmic dissipation. In the Hall effect, differential rotation of the electron…
We investigate the long-time evolution of magnetic fields generated by the two-stream instability at ultra- and sub-relativistic astrophysical collisionless shocks. Based on 3D PIC simulation results, we introduce a 2D toy model of…
Current sheets are spatially localized almost-1D structures with intense plasma currents. They play a key role in storing the magnetic field energy and they separate different plasma populations in planetary magnetospheres, the solar wind,…
We study the magnetic field and current structure associated with a coronal loop. Through this we investigate to what extent the assumptions of a force-free magnetic field break down and where they might be justified. We analyse a 3D MHD…
This paper is the first in a series aimed at understanding the long-term evolution of neutron star magnetic fields. We model the stellar matter as an electrically neutral and lightly ionized plasma composed of three moving particle species:…
We present initial results from the first 3-dimensional numerical magnetohydrodynamical (MHD) simulations of magnetic field evolution in merging clusters of galaxies. Within the framework of idealized initial conditions similar to our…
We investigate the internal structure of the current sheet in the pulsar wind within force-free and two-fluid MHD approximations. Within the force-free approximation we obtain general asymptotic solution of the Grad-Shafranov equation for…
In space and astrophysical plasmas turbulence leads to the development of coherent structures characterized by a strong current density and important magnetic shears. Using hybrid-kinetic simulations of turbulence (3D with different energy…