Browsing Natural and Agricultural Sciences by Subject "Heliosphere"

Now showing items 1-10 of 18

    • Acceleration of cosmic rays in the outer heliosphere 

      Prinsloo, Phillip Lourens (North-West University (South Africa), Potchefstroom Campus, 2016)
      Shortly before the Voyager spacecraft crossed the heliospheric termination shock, they encountered narrow, peak-like enhancements in the intensities of low-energy electrons. These enhancements were associated at the time ...

    • Aspects of the time-dependent modulation of galactic cosmic rays throughout a three-dimensional heliosphere 

      Mohlolo, Selwana Timothy (North-West University (South Africa), 2021)
      A dominant feature in the heliosphere is the heliospheric current sheet, separating regions of opposite polarity of the heliospheric magnetic field. This structure is dependent on solar activity through the tilt angle, ...

    • Cosmic ray modulation processes in the heliosphere 

      Vos, Etienne Eben (North-West University, 2011)
      The solar minimum of 2009 has been identified as an exceptional event with regard to cosmic ray (CR)modulation, since conditions in the heliosphere have reached unprecedented quiet levels. This unique minimum has been ...

    • Effects of termination shock acceleration on cosmic rays in the heliosphere 

      Langner, Ulrich Wilhelm (North-West University, 2004)
      The interest in the role of the solar wind termination shock (TS) and heliosheath in cosmic ray (CR) modulation studies has increased sigm6cantly as the Voyager 1 and 2 spacecraft approach the estimated position of the TS. ...

    • Modelling charge-sign dependent modulation of cosmic rays in the heliosphere 

      Vos, Etienne Eben (North-West University (South Africa), 2016)
      The solar minimum of cycle 23/24 has seen exceptionally quiet levels of solar activity and heliospheric modulation, which resulted in the highest cosmic ray (CR) spectrum ever recorded at Earth in December 2009 by the ...

    • Modelling of cosmic ray modulation in the heliosphere by stochastic processes 

      Strauss, Roelf du Toit (North-West 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, ...

    • Modelling of galactic and jovian electrons in the heliosphere 

      Moeketsi, Daniel Mojalefa (North-West University, 2004)
      A three-dimensional (3D) steady-state electron modulation model based on Parker (1965) transport equation is applied to study the modelling of – 7 MeV galactic and Jovian electrons in the inner heliosphere. The latter ...

    • Modelling of galactic cosmic ray electrons in the heliosphere 

      Nndanganeni, Rendani Rejoyce (North-West University, 2012)
      The Voyager 1 spacecraft is now about 25 AU beyond the heliospheric termination shock and soon it should encounter the outer boundary of the heliosphere, the heliopause. This is set to be at 120 AU in the modulation model ...

    • Modelling of the heliosphere and cosmic ray transport 

      Snyman, Jasper Lodewyk (North-West University, 2007)
      A two dimensional hydrodynamic model describing the solar wind interaction with the local interstellar medium, which surrounds the solar system, is used to study the heliosphere both as a steady-state- and dynamic structure. ...

    • The modulation of galactic cosmic rays over a solar cycle 

      Mohlolo, Selwana Timothy (North-West University (South Africa), 2016)
      This work studied the modulation of galactic cosmic rays in the heliosphere by using a well-established, time dependent numerical modulation model to calculate cosmic ray transport inside the heliosphere over a solar ...