木星磁层熵参量的计算与分析

卢斌; 陈出新

doi:10.11728/cjss2013.05.465

木星磁层熵参量的计算与分析

doi: 10.11728/cjss2013.05.465

卢斌,
陈出新^,

中国科学技术大学地球和空间科学学院中国科学院近地空间环境重点实验室合肥 230026

基金项目: 国家自然科学基金项目(41074118, 40890163, 41121003);中国科学院重点研究项目(KZZD-EW-01-4)和中国科学院知识创新项目 (KZCX2-EW-QN50)共同资助

详细信息

作者简介:
卢斌, E-mail: ac21b@mail.ustc.edu.cn

通讯作者:
陈出新,E-mail:chuxin@ustc.edu.cn

中图分类号: P353
计量
- 文章访问数: 1911
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- 被引次数: 0
出版历程
- 收稿日期: 2012-11-02
- 修回日期: 2013-03-22
- 刊出日期: 2013-09-15

Entropy Parameter of Jupiter’s Magnetosphere

Lu Bin,
Chen Chuxin^,

CAS Key Laboratory of Basic Plasma Physics, School of Earth and Space Sciences, University ofScience and Technology of China, Hefei 230026

摘要

摘要: 空间等离子体熵的不守恒可能来自于磁场位形改变和非绝热过程.熵参量PV^5/3被广泛应用于分析地球磁层等离子体片中的输运问题,其中,P为压力,V为单位磁通量管的体积.通过熵参量的分布和变化可以判断磁层的稳定性及揭示磁层中的动力学过程.本文利用地球磁层中熵参量的分析应用,计算了木星稳态磁层模型中磁通量管的熵参量分布.从5R_j(R_j为木星半径)到55R_j,熵参量增加了4个量级,55R_j之后有所下降,表明所用磁层模型在55R_j之外已经不稳定.同时,假想磁场重联后的单位磁通量管的熵参量分布表明,赤道面中远磁尾的磁场重联是由尾向输运的磁力线管拉伸断裂重联引起的.
- 木星 /
- 磁层 /
- 熵参量 (PV^5/3) /
- 重联
Abstract: The nonconservation of entropy in space plasmas can result from magnetic reconfiguration as well as nonadiabatic processes such as plasma transport and energy transport. The theory of plasma transport in Earth's plasma sheet depends critically on the entropy parameter PV^5/3, where P is particle pressure and V is the volume of a closed flux tube containing one unit of magnetic flux. The stability and dynamics of the magnetosphere could be indicated by the change of entropy parameter. This paper shows the distribution of entropy parameter in the Jupiter's stable magnetosphere model using the analysis method in Earth's plasma sheet. The entropy parameter increases by four order of magnitudes quickly between 5R_j and 55R_j and then decline slowly. The result shows that the magnetosphere is unstable beyond 55R_j. The paper also shows the contour of the entropy parameter after the fictitious magnetic reconnection. It points out that the reconnection near the equatorial plane is caused by the rupture and reconnection of the flux tube which transports tailward.
- Jupiter /
- Magnetosphere /
- Entropy parameter (PV^5/3) /
- Reconnection

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参考文献(15)

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