SHINE: Numerical Modeling of SHINE Campaign Events by Means of Coupled MagnetoHydroDynamics-Solar Energetic Particle (MHD-SEP) Simulations

该提案寻求资金，以提高我们对太阳爆发和相关太阳高能粒子（SEP）事件（重点是SHINE运动事件）的理解，通过MHD-SEP耦合数值模拟。利用最先进的3D磁流体动力学（MHD）代码BATS-R-US，加上密歇根大学最近开发的新粒子代码FLAMPA（粒子加速场线平流模型），提出者计划对选定的SEP事件进行详细研究，以解决以下基本问题：(1)太阳爆发是如何开始的，它们是如何演变的？(2)太阳粒子是如何加速和传输的？虽然人们普遍认为，最大的SEP事件是由cme驱动的行星际空间冲击造成的，但cme驱动的冲击与耀斑相关的太阳粒子加速的相对重要性是一个活跃的研究和辩论领域。这场争论的部分原因是我们对内日冕的激波演化的不完全理解，以及那里遇到的条件如何导致SEP变化，特别是与空间天气相关的高能量。只有对整个日冕的日冕抛射进行详细的建模才能澄清这些问题。PI将开发这些事件的三维数值模型，以研究相关喷发的动力学。特别是，这项工作将研究cme驱动的冲击形成的距离太阳有多近；这些冲击波的强度和几何形状如何随时间变化；以及激波特性的随时间变化如何解释观察到的逐渐发生的SEP事件的特征。BATS-R-US代码的自适应网格能力将允许PI在太阳附近获得足够高的数值分辨率，以跟踪CME和激波演化。另一方面，FLAMPA代码将使PI能够在cme驱动的冲击下检查太阳粒子（从质子到重离子的铁）随时间的传输和扩散加速度。这些数值研究的结果将与SoHO、Wind、ACE和GOES卫星的现有数据进行比较，以验证和改进模型。这将是第一个三维的、耦合的MHD-SEP研究，重点是了解日冕内cme驱动的冲击的形成和演化，以及它们在引起观测到的SEP变化中的作用。

This proposal seeks funds to improve our understanding of solar eruptions and related solar energetic particle (SEP) events (with a focus on SHINE Campaign Events), by means of coupled MHD-SEP numerical simulations. Using the state-of-the-art 3D MagnetoHydroDynamic (MHD) code BATS-R-US, coupled with a new particle code called FLAMPA (Field-Line-Advection Model for Particle Acceleration) recently developed at the University of Michigan, the proposers plan to perform detailed studies of selected SEP events in order to address the following fundamental questions: (1) How are solar eruptions initiated and how do they evolve? (2) How are solar particles accelerated and transported? While it is generally accepted that the largest SEP events result from CME-driven shocks in interplanetary space, the relative importance of CME-driven shocks versus flare-associated acceleration of solar particles is an area of active research and debate. Part of this debate arises from our incomplete understanding of shock evolution in the inner corona, and how the conditions encountered there may contribute to SEP variability, especially at high energies relevant for space weather. Only detailed modeling of CMEs throughout the corona can clarify these issues.The PI will develop three-dimensional numerical models of these events to investigate the dynamics of associated eruptions. In particular, this effort will study how close to the Sun CME-driven shocks form; how the strengths and geometries of these shock waves vary in time; and how the time-dependent changes in shock properties explain the observed signatures of gradual SEP events. The BATS-R-US code's adaptive grid capability will allow the PI to achieve sufficiently high numerical resolution near the Sun to follow CME and shock evolution. The FLAMPA code, on the other hand, will enable the PI to examine the time-dependent transport and diffusive acceleration of solar particles (from protons to the heavy ions of iron) at the CME-driven shocks.The results of these numerical investigations will be compared with the available data from SoHO, Wind, ACE, and GOES satellites in order to validate and improve the models. These will be the first three-dimensional, coupled MHD-SEP studies focused on understanding the formation and evolution of CME-driven shocks in the inner corona and their role in causing the observed SEP variability.