We formulate the problem of magnetic field dissipation during the accretion phase of low-mass star formation, and we carry out the first step of an iterative solution procedure by assuming that the gas is in free-fall along radial field lines. This so-called “kinematic approximation” ignores the back reaction of the Lorentz force on the accretion flow. In quasi steady-state, and assuming the re...

It is shown that the eigenvalue problem for the hermitian Wilson-Dirac operator of for a uniform magnetic field in two dimensions can be reduced to one-dimensional problem described by a relativistic analog of the Harper equation. An explicit formula for the secular equations is given in term of a set of polynomials. The spectrum exhibits a fractal structure in the infinite volume limit. An exa...

A nonperturbative technique is used to calculate the magnetoresistance of two-dimensional electron gases ~2DEG! subjected to a spatially periodic magnetic field B1 with period a in addition to a uniform magnetic field B0 in the same direction. For small amplitude modulation, magnetoresistance exhibits oscillations similar to the Weiss oscillations observed in 2DEG under spatially periodic elect...

The flow and heat transfer characteristics for natural convection along an inclined plate in a saturated porous medium with an applied magnetic field have been studied. The fluid viscosity has been assumed to be an inverse function of temperature. Assuming temperature vary as a power function of distance. The transformed ordinary differential equations have solved by numerical integration using...

In this contribution we report the results obtained using a newly developed self-consistent fully 3D Particle-In-Cell code for modelling of plasma-solid interaction. The model presented here involves a hollow cylindrical chamber opened to the plasma, with an external magnetic field limiting access of charged particles to the cylindrical wall. This model layout might provide more insight into pr...

We report measurements of millimeter wave emission from a rippled-field magnetron (crossed-field FEL). This is a novel source of coherent radiation in which electrons move in quasi-circular orbits under the combined action of a radial electric field, a uniform axial magnetic field and an azimuthally periodic wiggler magnetic field. We observe %300kW of RF power in a spectral line whose frequenc...