NSWP: Numerical Investigation of Coronal Mass Ejection (CME) Cannibalism in the Inner Heliosphere and Its Implications for Space Weather

首席研究员（PI）将在空间天气背景下研究CME-CME相互作用和CME自相残杀，重点是在复杂事件和CME驱动冲击波形成和演变期间更准确地预测1 AU的空间环境条件。PI的动机是观察到连续的地球日冕物质抛射（cme）的相互作用与大的、长时间的地磁风暴和大的渐进式太阳高能粒子（SEP）事件有关。该团队将对过去的CME事件进行详细的3D MHD数值研究，以解决基础科学问题。这些问题包括：前几次日冕抛射对于预调节日球层和修改太阳-L1磁连接的重要性；L1的原位测量如何与日冕抛射到达地球途中遇到的相互作用联系起来；连续日冕抛射与大型SEP事件的关联是否仅仅是统计上的，或者可以根据冲击的特征来理解，并与初始日冕抛射对日冕的破坏有关。该团队将从他们的3D MHD模拟中直接计算可观测到的数量，然后将模型输出与航天器观测结果进行比较。该项目将改进所使用的数值模型，从而使空间气象界能够解决与地球空间中一些最大和持续时间最长的干扰有关的问题。改进后的模型最终将通过空间天气建模框架交付给社区协调建模中心（CCMC），供太阳和日球圈社区更广泛地使用。该团队还将生成太阳现象的3D可视化和动画，用于夏威夷大学天文研究所（IfA）的公共宣传和教育项目。

The Principal Investigator (PI) will study CME-CME interactions and CME cannibalism in the context of space weather, focusing on more accurate prediction of space environment conditions at 1 AU during complex events and during the formation and evolution of CME-driven shock waves. The PI is motivated by the observation that the interaction of successive Earthbound Coronal Mass Ejections (CMEs) is associated with large, long-lived geomagnetic storms and large gradual solar energetic particle (SEP) events. The team will perform detailed 3D MHD numerical studies of past CME events in order to address fundamental science questions. Such questions include the importance of preceding CMEs for preconditioning the heliosphere and modifying the Sun-to-L1 magnetic connection, how in situ measurements at L1 relate to the interactions a CME encounters on its way to Earth, and whether the association of successive CMEs with large SEP events is merely statistical, or can be understood in terms of shocks' characteristics and related to the disruption of the corona by the initial CMEs. The team will compute directly observable quantities from their 3D MHD simulations, and then compare this model output with spacecraft observations. This project will result in improvements to the numerical models being used and thus enable the space weather community to tackle problems related to some of the largest and longest lived disruptions in geospace. The improved models will ultimately be delivered to the Community Coordinated Modeling Center (CCMC), via the Space Weather Modeling Framework, for broader use by the solar and heliospheric community. The team will also generate 3D visualizations and animations of solar phenomena for use in public outreach and education programs within the University of Hawaii's Institute for Astronomy (IfA).