Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath  

作　　者：Jin Guo TianRan Sun San Lu QuanMing Lu Yu Lin XueYi Wang Chi Wang RongSheng Wang Kai Huang 

机构地区：[1]School of Earth and Space Sciences,University of Science and Technology of China,Hefei 230026,China [2]CAS Center for Excellence in Comparative Planetology/CAS Key Lab of Geospace Environment,University of Science and Technology of China,Hefei 230026,China [3]Collaborative Innovation Center of Astronautical Science and Technology,Harbin 150001,China [4]National Space Science Center,Chinese Academy of Sciences,Beijing 100190,China [5]Physics Department,Auburn University,Auburn,AL,USA

出　　处：《Earth and Planetary Physics》2024年第1期47-58,共12页地球与行星物理（英文版）

基　　金：supported by the National Natural Science Foundation of China(NNSFC)grants 42074202,42274196;Strategic Priority Research Program of Chinese Academy of Sciences grant XDB41000000;ISSI-BJ International Team Interaction between magnetic reconnection and turbulence:From the Sun to the Earth。

摘　　要：Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.

关 键 词：MAGNETOPAUSE X-ray emissivity X-ray imaging SMILE global hybrid-PIC simulation 

分 类 号：P172.2[天文地球—天文学]