78 citations · 396 across the 21 of their papers we have counts for
21 papers
On the onset delays of solar energetic electrons and protons: Evidence for a common accelerator
R. D. Strauss, N. Dresing, I. G. Richardson +2
The processes responsible for the acceleration of solar energetic particles (SEPs) are still not well understood, including whether SEP electrons and protons are accelerated by com…
The radiation environment over the African continent at aviation altitudes: First results of the RPiRENA-based dosimeter
M. G. Mosotho, R. D. Strauss, S. Bottcher +1
The radiation environment over the African continent, at aviation altitudes, remains mostly uncharacterized and unregulated. In this paper we present initial measurements made by a…
The modulation of anomalous and galactic cosmic ray oxygen over successive solar cycle minima
R. D. Strauss, R. A. Leske, J. S. Rankin
Both the recent 2009 and 2020 solar minima were classified as unusually quiet and characterized with unusually high galactic cosmic ray (GCR) levels. However, unlike the trends fro…
Focused Space Weather Strategy for Securing Earth, and Human Exploration of the Moon and Mars
A. Posner, N. Arge, K. Cho +12
This white paper recognizes gaps in observations that will, when addressed, much improve solar radiation hazard and geomagnetic storm forecasting. Radiation forecasting depends on…
The radial variation of the solar wind turbulence spectra near the kinetic break scale from Parker Solar Probe measurements
S. Lotz, A. E. Nel, R. T. Wicks +7
In this study we examine the radial dependence of the inertial and dissipation range indices, as well as the spectral break separating the inertial and dissipation range in power d…
First results from the ENTOTO neutron monitor: Quantifying the waiting time distribution
R. D. Strauss, Nigussie M. Giday, Ephrem B. Seba +5
We discuss a newly established neutron monitor station installed at the ENTOTO Observatory Research Center outside of Addis Ababa, Ethiopia. This is a version of a mini-neutron mon…
Cosmic ray transport near the Sun
R. D. Strauss, J. P. van den Berg, J. S. Rankin
The strongly diverging magnetic field lines in the very inner heliosphere, through the associated magnetic focusing/mirroring forces, can, potentially, lead to highly anisotropic g…
Anomalous Cosmic Ray Oxygen Observations in to 0.1 au
Jamie S. Rankin, David J. McComas, Richard A. Leske +10
The Integrated Science Investigation of the Sun instrument suite onboard NASA's Parker Solar Probe mission continues to measure solar energetic particles and cosmic rays closer to…
The updated SANAE neutron monitor
R. D. Strauss, C. van der Merwe, C. Diedericks +5
Neutron monitors have been the premier ground-based instruments for monitoring the near-Earth cosmic ray flux for more than 70 years. It is essential to continue with such measurem…
On the residence-time of Jovian electrons in the inner heliosphere
A. Vogt, N. E. Engelbrecht, R. D. Strauss +3
Jovian electrons serve as an important test-particle distribution in the inner heliosphere and have been used extensively in the past to study the (diffusive) transport of cosmic r…
On the shape of SEP electron spectra: The role of interplanetary transport
R. Du Toit Strauss, Nina Dresing, Alexander Kollhoff +1
We address the effect of particle scattering on the energy spectra of solar energetic electron events using i) an observational and ii) a modeling approach. i) We statistically stu…
Voyager 2 enters interstellar space
R. Du Toit Strauss
After 41 years of travel, the Voyager 2 spacecraft joins its twin in interstellar space. A suite of papers report Voyager 2's experience of its transition through the heliosheath a…
Acceleration of solar wind particles by traveling interplanetary shocks
P. L. Prinsloo, R. D. Strauss, J. A. le Roux
The acceleration of thermal solar wind protons at spherical interplanetary shocks driven by coronal mass ejections is investigated. The solar wind velocity distribution is represen…
Solar energetic particle propagation in wave turbulence and the possibility of wave generation
R. D. Strauss, J. A. le Roux
A complete theory for the complex interaction between solar energetic particles and the turbulent interplanetary magnetic field remains elusive. In this work we aim to contribute t…
Perpendicular Diffusion of Solar Energetic Particles: Model Results and Implications for Electrons
R. D. Strauss, N. Dresing, N. E. Engelbrecht
The processes responsible for the effective longitudinal transport of solar energetic particles (SEPs) are still not completely understood. We address this issue by simulating SEP…
On Aspects Pertaining to the Perpendicular Diffusion of Solar Energetic Particles
R. D. Strauss, H. Fichtner
The multitude of recent multi-point spacecraft observations of solar energetic particle (SEP) events have made it possible to study the longitudinal distribution of SEPs in great d…
Acceleration of galactic electrons at the solar wind termination shock and Voyager 1 observations
M. S. Potgieter, P. L. Prinsloo, R. D. Strauss
Diffusive shock acceleration (DSA), as an acceleration process for Galactic electrons at the solar wind termination shock (TS), is investigated with a comprehensive numerical model…
On the Pulse Shape of Ground Level Enhancements
R. D. Strauss, O. Ogunjobi, H. Moraal +2
We study the temporal intensity profile, or pulse shape, of cosmic ray ground level enhancements (GLEs) by calculating the rise and decay times fo…
Comic ray flux anisotropies caused by astrospheres
K. Scherer, R. D. Strauss, S. E. S. Ferreira +1
Huge astrospheres or stellar wind bubbles influence the propagation of cosmic rays at energies up to the TeV range and can act as small-scale sinks decreasing the cosmic ray flux.…
The effect of magnetic field modifications on the modulation of cosmic rays in the heliosphere
J. L. Raath, M. S. Potgieter, R. D. Strauss +1
A numerical model for the solar modulation of cosmic rays, based on the solution of a set of stochastic differential equations, is used to illustrate the effects of modifying the h…
A Generalized Diffusion Tensor for Fully Anisotropic Diffusion of Energetic Particles in the Heliospheric Magnetic Field
Frederic Effenberger, Horst Fichtner, Klaus Scherer +3
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,…