Moysey Brio

The role of cosmic-ray-modified contact discontinuities and pressure balance structures in two-fluid cosmic-ray hydrodynamics in one Cartesian space dimension are investigated by means of analytic and numerical solution examples, as well as by weakly nonlinear asymptotics. The fundamental wave modes of the two-fluid cosmic-ray hydrodynamic equations in the long-wavelength limit consist of the backward and forward propagating cosmic-ray-modified sound waves,

In this work, we propose a new moving frame FDTD method based on the use of transformation optics (TO). Using TO, the time dependent Maxwell's equations are invariant but become magneto-electric in the moving frame and can be solved by a magneto-electric Maxwell solver. Previous proposed moving frame FDTD methods, such as the Lagrangian frame FDTD method, only transform the independent variables of the Maxwells equations that lead to instability due to numerical discretization of the additional advection terms introduced by the transformation and the PML boundary. In contrast, our method transform dependent and independent variables of the Maxwells equations to obtain an invariant form (no additional advection terms are introduced) so that instability problem is avoided. Numerical examples are presented to test the performance of our method.

In this paper we present a numerical method for solving a three-dimensional cold-plasma system that describes electron gas dynamics driven by an external electromagnetic wave excitation. The nonlinear Drude dispersion model is derived from the cold-plasma fluid equations and is coupled to the Maxwell’s field equations. The Finite-Difference Time-Domain (FDTD) method is applied for solving the Maxwell’s equations in conjunction