Comparison between magnetic coplanarity and MVA methods in determining the normal of Venusian bow shock  

作　　者：SHAN LiCan LU QuanMing ZHANG TieLong GAO XinLiang HUANG Can SU YanQing WANG Shui 

机构地区：[1]CAS Key Laboratory of Basic Plasma Physics, Department of Geophysics and Planetary Science, University of Science and Technology of China

出　　处：《Chinese Science Bulletin》2013年第20期2469-2472,共4页

基　　金：supported by Ocean Public Welfare Scientific Research Project, State Oceanic Administration People’s Republic of China (201005017);the National Natural Science Foundation of China (40931053,41174124, 41274144 and 41121003);the Fundamental Research Funds for the Central Universities (WK2080000010)

摘　　要：With the measurements of magnetic field of Venus Express (VEX), magnetic coplanarity and minimum variance analysis (MVA) methods are analyzed and their validity is tested to determine the normal of Venusian bow shocks. It is found that MVA method is the better than magnetic coplanarity, and 95% shock crossings can be accurately determined by the method. However, the occurrence of the shock normal which is not determined accurately by magnetic coplanarity increases with the decrease of the solar zenith angle (SZA). At the same time, compared with quasi-parallel shocks, there is more occurrence of the shock normal which cannot be determined accurately by magnetic coplanarity for quasi-perpendicular shocks.With the measurements of magnetic field of Venus Express （VEX）, magnetic coplanarity and minimum variance analysis （MVA） methods are analyzed and their validity is tested to determine the normal of Venusian bow shocks. It is found that MVA method is the better than magnetic coplanarity, and 95% shock crossings can be accurately determined by the method. However, the occurrence of the shock normal which is not determined accurately by magnetic coplanarity increases with the decrease of the solar zenith angle （SZA）. At the same time, compared with quasi-parallel shocks, there is more occurrence of the shock normal which cannot be determined accurately by magnetic coplanarity for quasi-perpendicular shocks.

关 键 词：共面性 MVA 金星 激波 定正 太阳天顶角 测量方法 方差分析 

分 类 号：O441.4[理学—电磁学]