Invariant Modulation of IMF Clock Angle on the Solar Wind Energy Input into the Magnetosphere  

作　　者：HAN Jinpeng LI Hui TANG Binbin WANG Chi 

机构地区：[1]State Key Laboratory of Space Weather,National Space Science Center,Chinese Academy of Sciences [2]College of Earth Science,University of the Chinese Academy of Sciences [3]Research and Development Center,China Academy of Launch Vehicle Technology

出　　处：《空间科学学报》2015年第6期673-678,共6页Chinese Journal of Space Science

基　　金：Supported by the National Basic Research Program(2012CB825602);National Natural Science Foundation of China(NNSFC,41204118,41231067);in part by the Specialized Research Fund for State Key Laboratories of China

摘　　要：By use of the global PPMLR Magnetohydrodynamics(MHD) model,a serial of quasisteady-state numerical simulations were conducted to examine the modulation property of the interplanetary magnetic field clock angle θ on the solar wind energy input into the magnetosphere.All the simulations can be divided into seven groups according to different criteria of solar wind conditions.For each group,37 numerical examples are analyzed,with the clock angle varying from 0° to 360° with an interval of 10°,keeping the other solar wind parameters(such as the solar wind number density,velocity,and the magnetic field magnitude) unchanged.As expected,the solar wind energy input into the magnetosphere is modulated by the IMF clock angle.The axisymmetrical bell-shaped curve peaks at the clock angle of 180°.However,the modulation effect remains invariant with varying other solar wind conditions.The function form of such an invariant modulation is found to be sin(0/2)^(2.70) + 0.25.By use of the global PPMLR Magnetohydrodynamics（MHD） model,a serial of quasisteady-state numerical simulations were conducted to examine the modulation property of the interplanetary magnetic field clock angle θ on the solar wind energy input into the magnetosphere.All the simulations can be divided into seven groups according to different criteria of solar wind conditions.For each group,37 numerical examples are analyzed,with the clock angle varying from 0° to 360° with an interval of 10°,keeping the other solar wind parameters（such as the solar wind number density,velocity,and the magnetic field magnitude） unchanged.As expected,the solar wind energy input into the magnetosphere is modulated by the IMF clock angle.The axisymmetrical bell-shaped curve peaks at the clock angle of 180°.However,the modulation effect remains invariant with varying other solar wind conditions.The function form of such an invariant modulation is found to be sin（0/2）2.70+ 0.25.

关 键 词：MHD simulation CLOCK ANGLE ENERGY input ENERGY cou 

分 类 号：P353.8[天文地球—空间物理学]