Dr
Donald Ngobeni
(1. Centre for Space Research, North-West University, Potchefstroom, South Africa; 2. School of Physical & Chemical Sciences, North-West University, Mmabatho, South Africa)
The global features of the modulation of galactic cosmic ray protons and helium nuclei are studied in the heliosphere from solar minimum to maximum activity with a comprehensive, three-dimensional, drift model and compared to proton and helium observations measured by PAMELA from 2006 to 2014. Combined with accurate very local interstellar spectra (VLIS) for protons and helium nuclei, this provides the opportunity to study in detail how differently the proton to helium ratio, over a wide range of rigidities, behaves towards increasing solar activity. In particular, the effects at the Earth of the difference in their VLIS’s, mass-to-charge ratio (A/Z) and those caused by the main modulation mechanisms will be illustrated from solar minimum to maximum activity.
Keywords
Cosmic rays · Heliosphere · Solar modulation ·
Solar activity · Galactic proton · Galactic helium
Subcategory |
Theoretical Results
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Dr
Donald Ngobeni
(1. Centre for Space Research, North-West University, Potchefstroom, South Africa; 2. School of Physical & Chemical Sciences, North-West University, Mmabatho, South Africa)
Dr
O.P.M Aslam
(Centre for Space Research, North-West University, Potchefstroom, South Africa)
Dr
Driaan Bisschoff
(Centre for Space Research, North-West University, Potchefstroom, South Africa)
Dr
Chris Ndiitwani
(1. Centre for Space Research, North-West University, Potchefstroom, South Africa; 2.School of Physical & Chemical Sciences, North-West University, Mmabatho, South Africa)
Prof.
Marius Potgieter
(Retired: FS4, Potchefstroom, South Africa)
Dr
Mirko Boezio
(INFN, Sezione di Trieste, I-34149 Trieste, Italy)
Mr
Nadir Marcelli
(INFN, Sezione di Rome, I-00133 Rome, Italy)
Dr
Riccardo Munini
(INFN, Sezione di Trieste, I-34149 Trieste, Italy)
Prof.
Vladimir Mikhailov
(National Research Nuclear University MEPHI, RU-115409 Moscow, Russia)