The relaxation dynamics of a magnetized plasma system is a subject of fundamental importance in magnetohydrodynamics—with applications ranging from laboratory plasma devices such as the toroidal-field pinch and spheromaks to astrophysical plasmas, stellar flaring activity, and coronal heating. Taylor in 1974 proposed that the magnetic field in a plasma, subject to certain constraints, relaxes t...

We describe a new method to include magnetic fields into smooth particle hydrodynamics. The derivation of the self-gravitating hydrodynamics equations from a variational principle is discussed in some detail. The non-dissipative magnetic field evolution is instantiated by advecting so-called Euler potentials. This approach enforces the crucial ∇·B = 0-constraint by construction. These recent de...

Solutions of physical equations which have non-trivial topological properties have been studied for already more than five years. As examples we may give the "monopole""2 and the ' ' in~tanton'~ in gauge field theories and the "pseudoparticle" in a two-dimensional isotropic f e r r ~ m a g n e t . ~ All these solutions a re characterized by some topological index: the magnetic charge of the mon...

The magnetohydrodynamical behavior (MHD) of accretion disks is reviewed. A detailed presentation of the fundamental MHD equations appropriate for protostellar disks is given. The combination of a weak (subthermal) magnetic field and Keplerian rotation is unstable to the magnetorotational instability (MRI), if the degree of ionization in the disk is sufficiently high. The MRI produces enhanced a...

Here, we demonstrate that polarization properties show a wide diversity depending on viewing angles. To simulate images of supermassive black hole and surrounding plasma, performed full-polarimetric general relativistic radiative transfer based three-dimensional magnetohydrodynamics models with moderate magnetic strengths. Under an assumption hot-jet cold-disk in the electron temperature prescr...

We present two generalized hybrid kinetic-Hall magnetohydrodynamics (MHD) models describing the interaction of a two-fluid bulk plasma, which consists thermal ions and electrons, with energetic, suprathermal ion populations described by Vlasov dynamics. The dynamics components are governed standard fluid equations in Hall MHD limit electron momentum equation providing an Ohm's law pressure term...

In this paper we describe an adaptive moving mesh technique and its application to convection-diffusion models from magnetohydrodynamics (MHD). The method is based on a coordinate transformation between physical and computational coordinates. The transformation can be viewed as a solution of adaptive mesh partial differential equations (PDEs) which are derived from the minimization of a mesh-en...