Time-dependent transport of energetic particles in magnetic turbulence: computer simulations versus analytical theory

Arendt, V.; Shalchi, A.

doi:10.1007/s10509-018-3338-6

Cited by 10 publications

(14 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, for compound sub-diffusion, one expects to find a non-Gaussian distribution function. This form, and therewith the result of Webb et al (2006), was confirmed via test-particle simulations by Arendt and Shalchi (2018) and can also be seen in Fig. 16 of this review.…”

Section: Compound Sub-diffusionsupporting

confidence: 79%

“…In the previous sections we discussed advanced systematic theories for perpendicular transport. As it was shown over the past few years, time-dependent UNLT theory in particular agrees with most test-particle simulations (see, e.g., Arendt and Shalchi 2018). However, there are two remaining questions which need to be explored.…”

Section: The Simplified Spectrummentioning

confidence: 58%

“…Previously, as quantitative theories were compared with simulations, it was often assumed that s = 5/3 and q = 3 (see for instance Arendt and Shalchi 2018). Therefore, we can easily show that…”

Section: Two-component Turbulence As An Examplementioning

confidence: 85%

“…(4.84) can easily be used in order to plot D versus time T . Equation (4.84) was originally derived in Arendt and Shalchi (2018) and is compared with simulations in Figs. 16 and 17 of this review.…”

Section: Modeling Parallel Diffusionmentioning

confidence: 99%

“…In the former case condition (9.1) is never satisfied leading to compound sub-diffusion as the final state. In the two-dimensional case parallel transport is not diffusive (see, e.g., Arendt and Shalchi 2018) violating the second rule.…”

Section: Further Commentsmentioning

confidence: 99%

See 4 more Smart Citations

Perpendicular Transport of Energetic Particles in Magnetic Turbulence

Shalchi

2020

Space Sci Rev

View full text Add to dashboard Cite

Scientists have explored how energetic particles such as solar energetic particles and cosmic rays move through a magnetized plasma such as the interplanetary and interstellar medium since more than five decades. From a theoretical point of view, this topic is difficult because the particles experience complicated interactions with turbulent magnetic fields. Besides turbulent fields, there are also large scale or mean magnetic fields breaking the symmetry in such systems and one has to distinguish between transport of particles parallel and perpendicular with respect to such mean fields. In standard descriptions of transport phenomena, one often assumes that the transport in both directions is normal diffusive but non-diffusive transport was found in more recent work. This is in particular true for early and intermediate times where the diffusive regime is not yet reached. In recent years researchers employed advanced numerical tools in order to simulate the motion of those particles through the aforementioned systems. Nevertheless, the analytical description of the problem discussed here is of utmost importance since analytical forms of particle transport parameters need to be known in several applications such as solar modulation studies or investigations of shock acceleration. The latter process is directly linked to the question of what the sources of high energy cosmic rays are, a problem which is considered to be one of the most important problems of the sciences of the 21st century. The present review article discusses analytical theories developed for describing particle transport across a large scale magnetic field as well as field line random walk. A heuristic approach explaining the basic physics of perpendicular transport is also presented. Simple analytical forms for the perpendicular diffusion coefficient are proposed which can easily be incorporated in numerical codes for solar modulation or shock acceleration studies. Test-particle simulations are also discussed together with a comparison with analytical results. Several applications such as cosmic ray propagation and diffusive shock acceleration are also part of this review.

show abstract

Section: Compound Sub-diffusionsupporting

confidence: 79%

Section: The Simplified Spectrummentioning

confidence: 58%

Section: Two-component Turbulence As An Examplementioning

confidence: 85%

Section: Modeling Parallel Diffusionmentioning

confidence: 99%

Section: Further Commentsmentioning

confidence: 99%

See 3 more Smart Citations

Perpendicular Transport of Energetic Particles in Magnetic Turbulence

Shalchi

2020

Space Sci Rev

View full text Add to dashboard Cite

show abstract

Theory of Cosmic Ray Transport in the Heliosphere

et al. 2022

View full text Add to dashboard Cite

Modelling the transport of cosmic rays (CRs) in the heliosphere represents a global challenge in the field of heliophysics, in that such a study, if it were to be performed from first principles, requires the careful modelling of both large scale heliospheric plasma quantities (such as the global structure of the heliosphere, or the heliospheric magnetic field) and small scale plasma quantities (such as various turbulence-related quantities). Here, recent advances in our understanding of the transport of galactic cosmic rays are reviewed, with an emphasis on new developments pertaining to their transport coefficients, with a special emphasis on novel theoretical and numerical simulation results, as well as the CR transport studies that employ them. Furthermore, brief reviews are given of recent progress in CR focused transport modelling, as well as the modelling of non-diffusive CR transport.

show abstract

Detailed test-particle simulations of energetic particles interacting with magnetized plasmas I. Two-component turbulence

Arendt

Shalchi

2020

Advances in Space Research

View full text Add to dashboard Cite

Time-dependent transport of energetic particles in magnetic turbulence: computer simulations versus analytical theory

Cited by 10 publications

References 55 publications

Perpendicular Transport of Energetic Particles in Magnetic Turbulence

Perpendicular Transport of Energetic Particles in Magnetic Turbulence

Theory of Cosmic Ray Transport in the Heliosphere

Detailed test-particle simulations of energetic particles interacting with magnetized plasmas I. Two-component turbulence

Contact Info

Product

Resources

About