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Hydrodynamical simulations are presented of a pulsar wind emitted by a supersonically moving pulsar. The pulsar moves through the interstellar medium or, in the more interesting case, through the supernova remnant created at its birth event. In both cases there exists a threefold structure consisting of the wind termination shock, contact discontinuity and(More)
Obtainable computational efficiency is evaluated when using an Adaptive Mesh Refinement (AMR) strategy in time accurate simulations governed by sets of conservation laws. For a variety of 1D, 2D, and 3D hydro-and magnetohydrodynamic simulations, AMR is used in combination with several shock-capturing, conservative discretization schemes. Solution accuracy(More)
We formulate general guidelines to extend an explicit code with a great variety of implicit and semi-implicit time integration schemes. The discussion is based on their speciic implementation in the Versatile Advection Code, which is a general purpose software package for solving systems of non-linear hyperbolic (and/or parabolic) partial diierential(More)
A complete analytical and numerical treatment of all magnetohydrodynamic waves and instabilities for radially stratified, magnetized accretion disks is presented. The instabilities are a possible source of anomalous transport. While recovering results on known hydrodynamic and both weak-and strong-field mag-netohydrodynamic perturbations, the full(More)
In many plasma physical and astrophysical problems, both linear and nonlinear effects can lead to global dynamics that induce, or occur simultaneously with, local phenomena. For example, a magnetically confined plasma column can potentially posses global magnetohydrody-namic (MHD) eigenmodes with an oscillation frequency that matches a local eigenfrequency(More)
Two scientiic application programs, the Versatile Advection Code and the HEating by Resonant Absorption code are adapted to parallel computer platforms. Both programs can solve the time dependent nonlinear partial diierential equations of magnetohydrodynamics with diierent numerical schemes. We describe our approach to parallelize the original Fortran 90(More)
The Versatile Advection Code is a general tool for solving hydrodynamical and magnetohydrodynamical problems arising in astrophysics. We compare the performance of the code on diierent computer platforms, including work stations and vector and parallel supercom-puters. Good parallel scaling can be achieved with the data parallelism expressed in High(More)