SHINE: Physics-based and Statistical Studies Connecting Surface-field Distributions to the Magnetic Flux Rope Structure in the Corona and Heliosphere

SHINE：基于物理和统计的研究将表面场分布与日冕和日光层的磁通绳结构联系起来

• 批准号: 2228967
• 负责人: Hong Xie
• 金额: $ 50.85万
• 依托单位: Catholic University of America
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-11-01 至 2025-10-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2228967&HistoricalAwards=false
• 关键词: SHINE; Physics; based; Statistical; Studies

Coronal mass ejections (CMEs) from the Sun are the driver of extreme space weather near Earth. This project addresses the Solar, Heliospheric, and Interplanetary Environment (SHINE) goal of understanding the origin and evolution of CMEs through an investigation of magnetic flux ropes. The project is led by scientists from under-represented groups in STEM, who will mentor undergraduate students from underrepresented ethnic minority groups or first-generation college students. The project advances the participation of women in science. Outreach will also be conducted in preparation for the October 2023 and April 2024 solar eclipses.The central goal of this project is to obtain a quantitative understanding of the structure and evolution of magnetic flux ropes from the solar photosphere to the inner heliosphere. The scientific objective of the work is to determine how the reconnected magnetic flux in the solar source region drives the CME flux rope structure in the corona and heliosphere. The proposed objective will be achieved by answering the questions: 1) Do flux ropes exist prior to eruptions, or are they formed during eruptions, or some combination of the two? 2) How magnetic reconnection affect the magnetic properties and kinematics of CME flux ropes? A combination of photospheric and coronal observations combined with flux rope fitting form the basis for geometrical and magnetic characterization of the “flux rope from eruption data” (FRED). The team will determine the direction of the axial magnetic field and magnetic flux rope (MFR) helicity by a combination of magnetogram data and EUV eruptive features (e.g., coronal arcade skews, Fe XII stalks, sigmoids, and magnetic tongues) in solar source regions. Since the flux rope legs are anchored in the photosphere within the EUV core dimming regions in the eruption site, the magnetic flux within the core dimming region corresponds to the flux rope’s axial flux. The reconnected flux within the post eruption arcade corresponds to the poloidal flux of the flux rope. Thus, a MFR is fully defined in the corona and its evolution is tracked under the assumption of self-similar expansion, enabling the prediction of the Bz (out of the ecliptic field) component that encounters Earth. The coronal flux rope structure will be compared against the flux rope in the heliosphere fitted to in-situ observations at various heliocentric distances (Parker Solar Probe, Solar Orbiter, and spacecraft near 1 AU), including self-similar expansion, helicity and the orientation of the coronal and interplanetary flux ropes. The team will use the elliptical flux rope and graduated cylindrical shell techniques for forward modeling of the CME flux ropes. Both the Lepping cylindrical force-free magnetic cloud fitting and Marubashi cylinder and torus fitting are used to derive the MFR structure in CMEs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

太阳的日冕物质抛射 (CME) 是地球附近极端太空天气的驱动因素，该项目旨在通过磁通量绳的研究来了解日冕物质抛射 (CME) 的起源和演化，从而实现太阳、日光层和行星际环境 (SHINE) 的目标。该项目由来自 STEM 领域代表性不足的群体的科学家领导，他们将指导来自代表性不足的少数族裔群体的本科生或第一代大学生，该项目还将促进女性参与科学。为 2023 年 10 月和 2024 年 4 月的日食做准备。该项目的中心目标是定量了解从太阳光球层到内日光层的磁通量绳的结构和演化。这项工作的科学目标是。确定太阳源区域中重新连接的磁通量如何驱动日冕和日光层中的 CME 磁绳结构 通过回答以下问题可以实现所提出的目标： 1) 磁绳在之前是否存在。 2) 磁重联如何影响日冕物质抛射磁力线的磁特性和运动学？光球和日冕观测与磁力线拟合的结合构成了几何和磁力线拟合的基础。 “来自喷发数据的磁通绳”（FRED）的磁特性该团队将通过结合磁图数据和磁通绳（MFR）确定轴向磁场的方向和磁通绳（MFR）螺旋度。太阳源区域的 EUV 喷发特征（例如日冕拱廊倾斜、Fe XII 茎、S 形和磁舌）由于磁通绳腿固定在喷发地点 EUV 核心调光区域内的光球层中，因此内部的磁通量。核心调光区域对应于磁通绳的轴向磁通，喷发后拱廊内的重新连接磁通对应于磁通的极向磁通。因此，MFR 在日冕中被完全定义，并在自相似膨胀的假设下跟踪其演化，从而能够预测与地球相遇的 Bz（黄道场外）分量。与安装在各种日心距离（帕克太阳探测器、太阳轨道器和接近 1 天文单位的航天器）的现场观测中的日光层磁通绳进行比较，包括自相似膨胀、螺旋度和该团队将使用椭圆磁通绳和分级圆柱壳技术对 CME 磁通绳进行正演建模，并使用 Lepping 圆柱无力磁云拟合和 Marubashi 圆柱和环面拟合。得出 CME 中的 MFR 结构。该奖项反映了 NSF 的法定使命，并且通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

What Do Halo CMEs Tell Us about Solar Cycle 25?

关于太阳周期 25，Halo 日冕物质抛射告诉我们什么？

• DOI: 10.3847/2041-8213/acdde2
• 发表时间: 2023-07
• 期刊: The Astrophysical Journal Letters
• 作者: Gopalswamy, Nat;Michalek, Grzegorz;Yashiro, Seiji;Mäkelä, Pertti;Akiyama, Sachiko;Xie, Hong
• 通讯作者: Xie, Hong