Browsing by Author "Strauss, Roelf du Toit"
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A generalized diffusion tensor for fully anisotropic diffusion of energetic particles in the heliospheric magnetic field
Barra, S.; Effenberger, F.; Fichtner, H.; Kleimann, J.; Scherer, K.; Strauss, Roelf du Toit (IOP publishing, 2012)The spatial diffusion of cosmic rays in turbulent magnetic fields can, in the most general case, be fully anisotropic, i.e., one has to distinguish three diffusion axes in a local, fieldaligned frame. We reexamine the ... 
Modeling ground and space based cosmic ray observations
Ferreira, Stephanus Esaias Salomon; Potgieter, Marthinus Steenkamp; Strauss, Roelf du Toit (Elsevier, 2012)After entering our local astrosphere (called the heliosphere), galactic cosmic rays, as charged particles, are affected by the Sun’s turbulent magnetic field. This causes their intensities to decrease towards the inner ... 
Modeling the acceleration and modulation of anomalous cosmic ray oxygen
Ferreira, Stephanus Esaias Salomon; Potgieter, Marthinus Steenkamp; Strauss, Roelf du Toit (Elsevier, 2011) 
Modelling heliospheric current sheet drift in stochastic cosmic ray transport models
Kopp, Andreas; Potgieter, Marthinus Steenkamp; Strauss, Roelf du Toit; Büsching, Ingo (Springer, 2012)Drifts are one of the major cosmic ray modulation mechanisms in the heliosphere. Three types of drifts occur in the background heliospheric magnetic field, namely curvature, gradient and current sheet drifts. The last ... 
Modelling of cosmic ray modulation in the heliosphere by stochastic processes / Roelf du Toit Strauss
Strauss, Roelf du Toit (NorthWest University, 2013)The transport of cosmic rays in the heliosphere is studied by making use of a newly developed modulation model. This model employes stochastic differential equations to numerically solve the relevant transport equation, ... 
On cosmic ray modulation beyond the heliopause: where is the modulation boundary?
Ferreira, Stephanus Esaias Salomon; Potgieter, Marthinus Steenkamp; Scherer, K.; Fichtner, H.; Strauss, Roelf du Toit; Fahr, H.J. (IOP Publications, 2011)Two of the paradigms in modeling the transport of galactic cosmic rays are that the modulation boundary is the heliopause and that the local interstellar spectra are identical to the galactic cosmic ray spectra. Here we ... 
On the propagation times and energy losses of cosmic rays in the heliosphere
Kopp, Andreas; Potgieter, Marthinus Steenkamp; Strauss, Roelf du Toit; Büsching, Ingo (American Geophysical Union, 2011)We present calculations of the propagation times and energy losses of cosmic rays as they are transported through the heliosphere. By calculating these quantities for a spatially 1D scenario, we benchmark our numerical ... 
A stochastic differential equation code for multidimensional FokkerPlanck type problems
Kopp, Andreas; Potgieter, Marthinus Steenkamp; Büsching, Ingo; Strauss, Roelf du Toit (Elsevier, 2012)We present a newly developed numerical code that integrates Fokker–Planck type transport equations in four to six spatial dimensions (configuration plus momentum space) and time by means of stochastic differential equations. ...