Complex Interaction of Reconnected Field Lines at Earth's Magnetopause Under Sub-Alfvénic Solar Wind With Northward Magnetic Field

IF 2.6 2区 地球科学 Q2 ASTRONOMY & ASTROPHYSICS
H. Hasegawa, R. E. Denton, L.-J. Chen, Q. Hu, M. N. Nishino, K.-J. Hwang
{"title":"Complex Interaction of Reconnected Field Lines at Earth's Magnetopause Under Sub-Alfvénic Solar Wind With Northward Magnetic Field","authors":"H. Hasegawa,&nbsp;R. E. Denton,&nbsp;L.-J. Chen,&nbsp;Q. Hu,&nbsp;M. N. Nishino,&nbsp;K.-J. Hwang","doi":"10.1029/2024JA033395","DOIUrl":null,"url":null,"abstract":"<p>We present observations on 24 April 2023 by the Magnetospheric Multiscale spacecraft at the dayside, mid-latitude magnetopause, when an interplanetary magnetic cloud (MC) with sub-Alfvénic flows and northward and dawnward interplanetary magnetic field components impacted Earth's magnetosphere. The aim is to reveal the processes of solar wind-magnetosphere interaction under sub-Alfvénic solar wind with northward magnetic field. Our analysis of electron and ion data suggests that magnetopause reconnection occurred near both polar cusps, forming boundary layers on closed magnetic field lines on both the solar wind (i.e., MC) and magnetospheric sides of the magnetopause. Grad-Shafranov, electron-magnetohydrodynamics, and polynomial reconstructions of magnetopause current layers show that local (equator-of-the-cusp) reconnection occurred in a sub-ion-scale magnetopause current sheet with a low magnetic shear angle (30°). Interestingly, the local reconnection was observed between the two (MC-side and magnetosphere-side) layers of closed field lines. It indicates that reconnected field lines from double cusp reconnection were interacting to induce another reconnection at the mid-latitude magnetopause. Our results suggest that magnetopause reconnection was more efficient or frequent under sub-Alfvénic solar wind with much lower beta plasma conditions than typical conditions. We discuss the role of such efficient reconnection in the formation of low-latitude boundary layers.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"129 12","pages":""},"PeriodicalIF":2.6000,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JA033395","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Geophysical Research: Space Physics","FirstCategoryId":"89","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1029/2024JA033395","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0

Abstract

We present observations on 24 April 2023 by the Magnetospheric Multiscale spacecraft at the dayside, mid-latitude magnetopause, when an interplanetary magnetic cloud (MC) with sub-Alfvénic flows and northward and dawnward interplanetary magnetic field components impacted Earth's magnetosphere. The aim is to reveal the processes of solar wind-magnetosphere interaction under sub-Alfvénic solar wind with northward magnetic field. Our analysis of electron and ion data suggests that magnetopause reconnection occurred near both polar cusps, forming boundary layers on closed magnetic field lines on both the solar wind (i.e., MC) and magnetospheric sides of the magnetopause. Grad-Shafranov, electron-magnetohydrodynamics, and polynomial reconstructions of magnetopause current layers show that local (equator-of-the-cusp) reconnection occurred in a sub-ion-scale magnetopause current sheet with a low magnetic shear angle (30°). Interestingly, the local reconnection was observed between the two (MC-side and magnetosphere-side) layers of closed field lines. It indicates that reconnected field lines from double cusp reconnection were interacting to induce another reconnection at the mid-latitude magnetopause. Our results suggest that magnetopause reconnection was more efficient or frequent under sub-Alfvénic solar wind with much lower beta plasma conditions than typical conditions. We discuss the role of such efficient reconnection in the formation of low-latitude boundary layers.

Abstract Image

亚阿尔夫萨奇太阳风与北磁场作用下地球磁层顶重连磁力线的复杂相互作用
本文介绍了2023年4月24日,磁层多尺度航天器在中纬度磁层顶的日侧观测到的一个带亚阿尔夫萨奇流的行星际磁云(MC)和向北和向南的行星际磁场分量撞击地球磁层的情况。目的是揭示在磁场向北的亚阿尔夫萨奇太阳风作用下的太阳风-磁层相互作用过程。我们对电子和离子数据的分析表明,磁层顶重联发生在两个极尖附近,在太阳风(即MC)和磁层顶磁层侧的封闭磁场线上形成边界层。磁层顶电流层的grada - shafranov、电子-磁流体力学和多项式重建表明,在低磁剪切角(30°)的亚离子尺度磁层顶电流层中发生了局部(尖端赤道)重联。有趣的是,在两个(mc侧和磁层侧)闭合场线层之间观察到局部重联。这表明在中纬度磁层顶,由双尖峰重联引起的重联磁力线相互作用引起了另一次重联。我们的研究结果表明,与典型的条件相比,在低β等离子体条件下,亚α - vsamac太阳风条件下磁层顶重联更有效或更频繁。我们讨论了这种有效的重联在低纬度边界层形成中的作用。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Journal of Geophysical Research: Space Physics
Journal of Geophysical Research: Space Physics Earth and Planetary Sciences-Geophysics
CiteScore
5.30
自引率
35.70%
发文量
570
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信