我们研究了垂直扩散在塑造共转相互作用区（CIRs）高能离子能谱中的作用，重点关注其质荷比（A/Q）依赖。我们使用 EUropean Heliospheric FORcasting Information Asset（EUHFORIA）模拟了一个合成 CIR，并通过求解同时包含平行扩散和垂直扩散的聚焦输运方程，对随后的离子加速与输运进行建模。结果揭示了在有、无垂直扩散两种情形下离子能谱的显著差异。在不存在垂直扩散时，CIR 附近的离子能谱表现出强烈的 (A/Q)^ε 依赖，其中 ε 取决于湍流谱指数，这与理论预测一致。相比之下，纳入具有弱 A/Q 依赖的垂直扩散后，不同离子种类产生了相似的能谱。这与 CIR 中高能粒子的观测结果在定性上相符。
英文摘要：
We investigate the role of perpendicular diffusion in shaping energetic ion spectrum in corotating interaction regions (CIRs), focusing on its mass-to-charge ($A/Q$) dependence. We simulate a synthetic CIR using the EUropean Heliospheric FORcasting Information Asset (EUHFORIA) and model the subsequent ion acceleration and transport by solving the focused transport equation incorporating both parallel and perpendicular diffusion. Our results reveal distinct differences in ion spectra between scenarios with and without perpendicular diffusion. In the absence of perpendicular diffusion, ion spectra near CIRs show a strong $(A/Q)^ε$ dependence with $ε$ depending on the turbulence spectral index, agreeing with theoretical predictions. In contrast, the incorporation of perpendicular diffusion, characterized by a weak $A/Q$ dependence, leading to similar spectra for different ion species. This qualitatively agrees with observations of energetic particles in CIRs.
Shear interaction and acceleration of a corotating stream detected by Parker Solar Probe
Universitá degli Studi di Firenze（佛罗伦萨大学）；INAF Osservatorio Astrofisico di Arcetri（意大利国家天体物理研究所阿切特里天文台）；Istituto di Astrofisica e Planetologia Spaziali (IAPS), Istituto Nazionale di Astrofisica (INAF)（意大利国家天体物理研究所空间天体物理学和行星学研究所）；Northumbria University（诺森比亚大学）；Institute of Atmospheric Physics of the Czech Academy of Sciences（捷克科学院大气物理研究所）；Astronomical Institute of the Czech Academy of Sciences（捷克科学院天文研究所）；Space Sciences Laboratory, University of California, Berkeley（加州大学伯克利分校空间科学实验室）
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The solar corona below 10 solar radii is an important region for early acceleration and transport of solar energetic particles (SEPs) by coronal mass ejection-driven shock waves. There, these waves propagate into a highly variable dynamic medium with steep gradients and rapidly expanding coronal magnetic fields, which modulates the particle acceleration near the shock or wave surfaces, and the way SEPs spread into the heliosphere. We present a study modelling the acceleration of SEPs in global coronal shock events in the corona, as well as their transport to 1 au, based on telescopic observati…
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Parametrisation of the wave-zonal flow interactions taking into account the full Coriolis acceleration. The necessity of going beyond the traditional approximation in the sub-inertial regime and in weakly stratified regions
Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM（巴黎萨克雷大学，巴黎西岱大学，法国原子能和替代能源委员会，法国国家科学研究中心，天体物理学与分子星际介质实验室）
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