Browsing Faculty of Natural and Agricultural Sciences by Author "Engelbrecht, N.E."

Now showing items 1-7 of 7

    • An AB initio model for cosmic-ray modulation 

      Engelbrecht, N.E.; Burger, R.A. (IOP Publishing, 2013)
      A proper understanding of the effects of turbulence on the diffusion and drift of cosmic rays (CRs) is of vital importance for a better understanding of CR modulation in the heliosphere. This study presents an ab initio ...

    • An AB initio model for the modulation of galactic cosmic-ray electrons 

      Engelbrecht, N.E.; Burger, R.A. (IOP Publishing, 2013)
      The modulation of galactic cosmic-ray electrons is studied using an ab initio three-dimensional steady state cosmicraymodulation code in which the effects of turbulence on both the diffusion and drift of these cosmic-rays ...

    • Cosmic-ray modulation: an ab initio approach 

      Engelbrecht, N.E.; Burger, R.A. (Springer Verlag, 2014)
      A better understanding of cosmic-ray modulation in the heliosphere can only be gained through a proper understanding of the effects of turbulence on the diffusion and drift of cosmic rays. We present an ab initio model ...

    • Effects of various dissipation range onset models on the 26-day variations of low-energy galactic cosmic-ray electrons 

      Engelbrecht, N.E.; Burger, R.A. (Elsevier, 2010)
      The effect of various models presented by Leamon et al. (2000) for the dissipation range cutoff wavenumber on the 26-day variations of galactic cosmic-ray electrons in a Fisk-Parker hybrid field is investigated, by means ...

    • A Fisk-Parker hybrid heliospheric magnetic field with a solar-cycle dependence 

      Burger, R.A.; Krüger, T.P.J.; Hitge, M.; Engelbrecht, N.E. (IOP Publishing, 2008)
      We present a refinement of the Fisk-Parker hybrid field of Burger and Hitge which now includes a region bordering the solar rotational equator where magnetic field footpoint motion occurs only through diffusive reconnection. ...

    • Possible evidence for a Fisk-type heliospheric magnetic field. 1. Analyzing Ulysses/Ket electron observations 

      Sternal, O.; Engelbrecht, N.E.; Burger, R.A.; Ferreira, S.E.S.; Potgieter, M.S.; Kopp, A. (IOP Publishing, 2011)
      The propagation of energetic charged particles in the heliospheric magnetic field is one of the fundamental problems in heliophysics. In particular, the structure of the heliospheric magnetic field remains an unsolved ...

    • Time-dependent cosmic ray modulation 

      Manuel, R.; Ferreira, S.E.S.; Potgieter, M.S.; Strauss, R.D.; Engelbrecht, N.E. (Elsevier, 2011)
      Time-dependent cosmic ray modulation is calculated over multiple solar cycles using our well established two-dimensional time-dependent modulation model. Results are compared to Voyager 1, Ulysses and IMP cosmic ray ...