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The shear flow instabilities under the presence of magnetic fields in the primordial disk can greatly facilitate the formation of density structures that serve as seeds prior to the onset of the gravitational Jeans instability. We evaluate the effects of the Parker, magnetorotational and kinematic dynamo instabilities by comparing the properties of these instabilities. We calculate the mass spectra of coagulated density structures by the above mechanism in the radial direction for an axisymmetric magnetohydrodynamic (MHD) torus equilibrium and power density profile models. Our local three-dimensional MHD simulation indicates that the coupling of the Parker and magnetorotational instability creates spiral arms and gas blobs in an accretion disk, reinforcing the theory and model. Such a mechanism for the early structure formation may be tested in a laboratory. The recent progress in experiments involving shear flows in rotating tokamak, field reversed configuration (FRC) and laser plasmas may become a key element to advance in nonlinear studies. [ABSTRACT FROM AUTHOR]

WINDMI-RC is a family of physics-based models that range in dimensiouality from low-order models of dimension d = 8, which model the flow of energy between the eight highest global energy components of the tail, to high-order models with dimension d ~ 100 or more, for models that resolve the nonlinear dynamics of the system into different latitude zones. The models are intrinsically three-dimensional in configuration space and use the basic geometry of the Tsyganenko magnetic field model to define the geometrical quantities. The models satisfy the constraints of the conservations laws of energy and electrical charge in their network of nodes and branches that follow from the structure of the system. These models describe the injection of plasma from the plasma sheet and across the Alfven layer into the inner ring current. The transport uses the storm-time solar wind dynamo electric field as the driver for the network model coupled to the inner magnetospheric corotation electric field. Index Terms--Magnetic storm, magnetosphere, ring current.

The nonlinear equations describing drift-Alfvén solitary vortices in a low β, rotating plasma are derived. Two types of solitary vortex solutions along with their corresponding nonlinear dispersion relations are obtained. Both solutions have the localized coherent dipolar structure. The first type of solution belongs to the family of the usual Rossby or drift wave vortex, while the second type of solution is intrinsic to the electromagnetic perturbation in a magnetized plasma and is a complicated structure. While the first type of vortex is a solution to a second-order differential equation the second one is the solution of a fourth-order differential equation intrinsic to the electromagnetic problem. The fourth-order vortex solution has two intrinsic space scales in contrast to the single space scale of the previous drift vortex solution. With the second short scale length the parallel current density at the vortex interface becomes continuous. As special cases the rotational electron drift vortex and the rotational ballooning vortex also are given. [ABSTRACT FROM AUTHOR]

The dissipative one-field drift wave equation is solved using the pseudospectral method to generate steady-state fluctuations. The fluctuations are analyzed in terms of space-time correlation functions and modal probability distributions. Nearly Gaussian statistics and exponential decay of the two-time correlation functions occur in the presence of electron dissipation, while in the absence of electron dissipation long-lived vortical structures occur. Formulas from renormalized, Markovianized statistical turbulence theory are given in a local approximation to interpret the dissipative turbulence. [ABSTRACT FROM AUTHOR]