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

被引:10
作者
Arendt, V. [1 ]
Shalchi, A. [1 ]
机构
[1] Univ Manitoba, Dept Phys & Astron, Winnipeg, MB R3T 2N2, Canada
基金
加拿大自然科学与工程研究理事会;
关键词
Diffusion; Magnetic fields; Turbulence; CHARGED-PARTICLES; PERPENDICULAR TRANSPORT; SUBDIFFUSIVE TRANSPORT; COSMIC-RAYS; FIELD LINES; RANDOM-WALK; DIFFUSION; ACCELERATION; SCATTERING; RECOVERY;
D O I
10.1007/s10509-018-3338-6
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We explore numerically the transport of energetic particles in a turbulent magnetic field configuration. A test-particle code is employed to compute running diffusion coefficients as well as particle distribution functions in the different directions of space. Our numerical findings are compared with models commonly used in diffusion theory such as Gaussian distribution functions and solutions of the cosmic ray Fokker-Planck equation. Furthermore, we compare the running diffusion coefficients across the mean magnetic field with solutions obtained from the time-dependent version of the unified non-linear transport theory. In most cases we find that particle distribution functions are indeed of Gaussian form as long as a two-component turbulence model is employed. For turbulence setups with reduced dimensionality, however, the Gaussian distribution can no longer be obtained. It is also shown that the unified non-linear transport theory agrees with simulated perpendicular diffusion coefficients as long as the pure two-dimensional model is excluded.
引用
收藏
页数:16
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