The X-ray corona is richly structured with individual plasma loops. A model is presented explaining these loops as the sites of magnetic energy storage and sporadic release. Energy is stored as coronal currents driven inductively by motions at the photosphere. These currents occur at internal boundaries in the coronal eld called separator. A method is described for completely characterizing the...

We study the one-dimensional system of Ginzburg-Landau equations that models a thin lm of superconductor subjected to a tangential magnetic eld. We prove that the bifurcation curve for the symmetric problem is the graph of a continuous function of the supremum of the order parameter. We also prove the existence of a critical magnetic eld. In general, there is more than one positive solution to ...

We show that the the cyclotron resonance in a two-dimensional electron gas has nontrivial properties if the correlation length of the disorder is larger than the de Broglie wavelength: (a) the linewidth depends di erently on the magnetic eld in strong, intermediate, and weak magnetic eld regimes (b) at the transition from the intermediate to the weak elds the linewidth suddenly collapses due to...

We present a numerical model of an accretion disc with mean-eld dynamo action that develops pressure-driven collimated outtow near the rotation axis and a centrifugally driven uncollimated wind in the outer parts. The jet is collimated and connned by the azimuthal magnetic eld that is produced by the dynamo in the disc and advected to the disc corona. The jet is hot and dense, but has low angul...

It is shown that the turbulent dynamo -e ect converts magnetic helicity from the turbulent eld to the mean eld when the turbulence is electromagnetic while the magnetic helicity of the meaneld is transported across space when the turbulence is electrostatic or due to the electron diamagnetic e ect. In all cases, however, the dynamo e ect strictly conserves the total helicity except for a batter...

We consider the modeling of strains generated by magnetostrictive materials in response to applied magnetic elds. The active or external component of the strain is due to the rotation of magnetic moments within the material to align with the applied eld. This is characterized through consideration of the Jiles-Atherton mean eld theory for ferromagnetic hysteresis in combination with a quadratic...

The protostellar outflow is star’s first cry at the moment of birth. The outflows have indispensable role in the formation of single stars, because they carry off the excess angular momentum from the centre of the shrinking gas cloud, and permits further collapse to form a star. On the other hand, a significant fraction of stars is supposed to be born as binaries with circumbinary disk that are...

Shear ow with an applied cross-stream magnetic eld is studied using dissipative incompressible magnetohydrodynamics. The study incorporates exact solutions, the energy stability method, and exact bounds on the total energy dissipation rate. Two physical con gurations are examined: magnetic Couette ow and Hartmann ow, the latter being Poiseuille ow with the existence of a perpendicular magnetic ...

Stellar jets are normally constituted by chains of knots with some periodicity in their spatial distribution, corresponding to a variability of order of several years in the ejection from the protostar/disk system. A widely accepted theory for the presence of knots is related to the generation of internal working surfaces due to variations in the jet ejection velocity. In this paper we study th...

Rotation measures of pulsars and extragalactic point sources have been known to reveal largescale antisymmetries in the Faraday rotation sky with respect to the Galactic plane and halo that have been interpreted as signatures of the mean magnetic field in the Galactic halo. We describe Faraday rotation measurements of the diffuse Galactic polarized radio emission over a large region in the nort...