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The role of radial perpendicular diffusion and latitude dependent acceleration along the solar
(Elsevier, 2008)
A numerical model, based on Parker’s transport equation, describing the modulation of anomalous cosmic rays and containing diffusive shock acceleration is applied. The role of radial perpendicular diffusion at the solar ...
Cosmic ray flux at the earth in a variable heliosphere
(Elsevier, 2008)
In recent years the variability of the cosmic ray flux has become one of the main issues not only for the interpretation of the abundances of cosmogenic isotopes in cosmochronic archives like, e.g., ice cores, but also for ...
Heliospace physics in South Africa: IHY 2007
(Elsevier, 2008)
An overview is given of research activities in South Africa related to the International Heliophysical Year in 2007. The emphasis is on Space Physics (Geospace and Heliospace). A short historical perspective is given, ...
Electron anisotropies in the inner heliosphere
(Elsevier, 2008)
A three-dimensional numerical model is used to study the propagation and modulation of a few MeV Jovian and galactic electrons in the inner heliosphere. The main aim of the work is to compute the three-dimensional electron ...
The variability of the proton cosmic ray flux on the sun's way around the galactic center
(Elsevier, 2008)
The discovery of direct evidences for the acceleration of high energetic particles at the shell supernova remnant RXJ1713.7-3946 underlined the need to calculate the cosmic ray (CR) distribution in the Galaxy on a spatial ...
A cosmic-ray positron anisotropy due to two middle-aged, nearby pulsars?
(IOP Publishing, 2008)
Geminga and B0656+14 are the closest pulsars with characteristic ages in the range of 100 kyr to 1 Myr. They both have spin-down powers of the order 3 × 1034 ergs s–1 at present. The winds of these pulsars had most probably ...
Constraints on the lepton content of PWN from the local CR positron spectrum
(ICRC, 2008)
Geminga is a nearby pulsar with an age of 3.42×105
yr and a spindown power of 3.2×1034
erg/s at present. B0656+14 has comparable spindown power, with an age of 1.11×105
yr and a distance
of 290 pc. The winds of these ...
Are anomalous cosmic rays the main contribution to the low-energy galactic cosmic ray spectrum?
(IOP Publishing, 2008)
While the high-energy part of the Galactic cosmic ray spectrum is well observed, its nature at energies below
about 1 GeV nucleon-1 is still not known well. Recent in situ measurements made with the Voyager 1 spacecraft
in ...
Cosmic rays in the dynamic heliosheath
(Elsevier, 2008)
Cosmic ray modulation in the outer heliosphere is discussed from a modeling perspective. Emphasis is on the transport and acceleration of these particles at and beyond the solar wind termination shock in the inner heliosheath ...
Solar cycle variations and cosmic rays
(Elsevier, 2008)
Cosmic rays are excellent indicators of the various solar cycle variations. Galactic and anomalous cosmic rays encounter an outward moving solar wind with cyclic magnetic-field fluctuations and turbulence, which constitute ...