Anisotropic diffusion of Galactic cosmic ray protons and their steady-state azimuthal distribution
Anisotropic diffusion of Galactic cosmic ray protons and their steady-state azimuthal distribution
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DOI：
10.1051/0004-6361/201220203
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发表时间：
2012-10
影响因子：
6.5
通讯作者：
F. Effenberger;H. Fichtner;K. Scherer;I. Busching
中科院分区：
文献类型：
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作者：
F. Effenberger;H. Fichtner;K. Scherer;I. Busching
宇宙射线的银河传输模型涉及这些粒子在星际介质中的扩散运动。由于大规模结构化的银河磁场，这种扩散相对于局部磁场方向是各向异性的。我们将这种输运效应以及连续损失过程纳入基于随机微分方程的宇宙射线质子银河传播定量模型中。我们计算了太阳银河轨道上不同位置的能谱，并将其与各向同性扩散情况进行比较。结果表明，在引入的各向异性扩散场景中获得了更大的变化幅度和不同的光谱形状，这反过来又强调了对精确银河磁场模型的需求。
Galactic transport models for cosmic rays involve the diffusive motion of these particles in the interstellar medium. Owing to the large-scale structured Galactic magnetic field, this diffusion is anisotropic with respect to the local field direction. We included this transport effect along with continuous loss processes in a quantitative model of Galactic propagation for cosmic ray protons that is based on stochastic differential equations. We calculated energy spectra at different positions along the Sun’s Galactic orbit and compared them to the isotropic diffusion case. The results show that a larger amplitude of variation and different spectral shapes are obtained in the introduced anisotropic diffusion scenario, which in turn emphasizes the need for accurate Galactic magnetic field models.