{"title":"非对称磁场再连接电子扩散区附近的能量通量密度分析","authors":"WANG Jun , ZHOU Meng , PANG Ye , DENG Xiao-hua","doi":"10.1016/j.chinastron.2024.03.005","DOIUrl":null,"url":null,"abstract":"<div><p>Magnetic reconnection is a crucial energy conversion process in plasmas, and it is important to study the forms of energy conversion and their distribution in this process. Previous research has focused mainly on the energy fluxes in symmetric reconnection, while the study of asymmetric reconnection at the Earth’s magnetopause, especially in terms of statistical analysis of multiple events, has not been reported before. Therefore, 10 magnetic reconnection events at the magnetopause observed by MMS (Magnetospheric Multiscale) satellite that passed through the electron diffusion region were used for analysis. Although the contribution of different energy flux varies case by case, our results show that in most events, the ion enthalpy flux is dominant, followed by the Poynting flux. The ion heat flux is slightly smaller than the Poynting flux, while the sum of ion kinetic energy flux, electron enthalpy flux and electron heat flux only accounts for less than 10% of the total energy flux. By projecting the normalized energy flux of all events into <span><math><mrow><msub><mi>B</mi><mi>L</mi></msub><mo>−</mo><msub><mi>V</mi><mrow><mo>(</mo><mi>i</mi><mo>,</mo><mi>L</mi><mo>)</mo></mrow></msub></mrow></math></span> plane (in <span><math><mrow><mi>L</mi><mi>M</mi><mi>N</mi></mrow></math></span> coordinate), we find that the energy flux in <span><math><mi>M</mi></math></span> direction is comparable to the energy flux in <span><math><mi>L</mi></math></span> direction and also there is an “anti-correlated” relationship between the ion velocity and ion heat flux around reconnection diffusion region, consistent with previous studies.</p></div>","PeriodicalId":35730,"journal":{"name":"Chinese Astronomy and Astrophysics","volume":"48 1","pages":"Pages 55-72"},"PeriodicalIF":0.0000,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0275106224000055/pdfft?md5=54057e4e235e3b92365b1a7869b94cd7&pid=1-s2.0-S0275106224000055-main.pdf","citationCount":"0","resultStr":"{\"title\":\"Analysis of the Energy Flux Density near Electron Diffusion Region of Asymmetric Magnetic Field Reconnection\",\"authors\":\"WANG Jun , ZHOU Meng , PANG Ye , DENG Xiao-hua\",\"doi\":\"10.1016/j.chinastron.2024.03.005\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Magnetic reconnection is a crucial energy conversion process in plasmas, and it is important to study the forms of energy conversion and their distribution in this process. Previous research has focused mainly on the energy fluxes in symmetric reconnection, while the study of asymmetric reconnection at the Earth’s magnetopause, especially in terms of statistical analysis of multiple events, has not been reported before. Therefore, 10 magnetic reconnection events at the magnetopause observed by MMS (Magnetospheric Multiscale) satellite that passed through the electron diffusion region were used for analysis. Although the contribution of different energy flux varies case by case, our results show that in most events, the ion enthalpy flux is dominant, followed by the Poynting flux. The ion heat flux is slightly smaller than the Poynting flux, while the sum of ion kinetic energy flux, electron enthalpy flux and electron heat flux only accounts for less than 10% of the total energy flux. By projecting the normalized energy flux of all events into <span><math><mrow><msub><mi>B</mi><mi>L</mi></msub><mo>−</mo><msub><mi>V</mi><mrow><mo>(</mo><mi>i</mi><mo>,</mo><mi>L</mi><mo>)</mo></mrow></msub></mrow></math></span> plane (in <span><math><mrow><mi>L</mi><mi>M</mi><mi>N</mi></mrow></math></span> coordinate), we find that the energy flux in <span><math><mi>M</mi></math></span> direction is comparable to the energy flux in <span><math><mi>L</mi></math></span> direction and also there is an “anti-correlated” relationship between the ion velocity and ion heat flux around reconnection diffusion region, consistent with previous studies.</p></div>\",\"PeriodicalId\":35730,\"journal\":{\"name\":\"Chinese Astronomy and Astrophysics\",\"volume\":\"48 1\",\"pages\":\"Pages 55-72\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S0275106224000055/pdfft?md5=54057e4e235e3b92365b1a7869b94cd7&pid=1-s2.0-S0275106224000055-main.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chinese Astronomy and Astrophysics\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0275106224000055\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"Physics and Astronomy\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chinese Astronomy and Astrophysics","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0275106224000055","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"Physics and Astronomy","Score":null,"Total":0}
引用次数: 0
摘要
磁重联是等离子体中一个重要的能量转换过程,研究这一过程中的能量转换形式及其分布非常重要。以往的研究主要集中在对称再连接中的能量通量,而对地球磁层顶非对称再连接的研究,尤其是对多个事件的统计分析,此前还未见报道。因此,我们利用 MMS(磁层多尺度)卫星在磁层顶观测到的穿过电子扩散区的 10 个磁再连接事件进行分析。尽管不同能量通量的贡献因情况而异,但我们的结果表明,在大多数事件中,离子焓通量占主导地位,其次是波因廷通量。离子热通量略小于波因廷通量,而离子动能通量、电子焓通量和电子热通量之和只占总能量通量的不到 10%。通过将所有事件的归一化能量通量投影到 BL-V(i,L) 平面(LMN 坐标),我们发现 M 方向的能量通量与 L 方向的能量通量相当,而且在再连接扩散区域周围,离子速度与离子热通量之间存在 "反相关 "关系,这与之前的研究一致。
Analysis of the Energy Flux Density near Electron Diffusion Region of Asymmetric Magnetic Field Reconnection
Magnetic reconnection is a crucial energy conversion process in plasmas, and it is important to study the forms of energy conversion and their distribution in this process. Previous research has focused mainly on the energy fluxes in symmetric reconnection, while the study of asymmetric reconnection at the Earth’s magnetopause, especially in terms of statistical analysis of multiple events, has not been reported before. Therefore, 10 magnetic reconnection events at the magnetopause observed by MMS (Magnetospheric Multiscale) satellite that passed through the electron diffusion region were used for analysis. Although the contribution of different energy flux varies case by case, our results show that in most events, the ion enthalpy flux is dominant, followed by the Poynting flux. The ion heat flux is slightly smaller than the Poynting flux, while the sum of ion kinetic energy flux, electron enthalpy flux and electron heat flux only accounts for less than 10% of the total energy flux. By projecting the normalized energy flux of all events into plane (in coordinate), we find that the energy flux in direction is comparable to the energy flux in direction and also there is an “anti-correlated” relationship between the ion velocity and ion heat flux around reconnection diffusion region, consistent with previous studies.
期刊介绍:
The vigorous growth of astronomical and astrophysical science in China led to an increase in papers on astrophysics which Acta Astronomica Sinica could no longer absorb. Translations of papers from two new journals the Chinese Journal of Space Science and Acta Astrophysica Sinica are added to the translation of Acta Astronomica Sinica to form the new journal Chinese Astronomy and Astrophysics. Chinese Astronomy and Astrophysics brings English translations of notable articles to astronomers and astrophysicists outside China.