基于同步轨道区磁场对相对论电子通量的预报

Prediction of Relativistic Electron Flux at Geosynchronous Orbit Based on Magnetic Field

地球同步轨道区相对论电子通量的变化与该区域的磁场分量P(垂直轨道面指向北)有很好的相关性,后者的变化相对于前者有1～2天的时间提前量,这为相对论电子通量的预报提供了可能.通过对二者相关性物理机制的研究.结合GOES11(135°W)卫星数据分析,确定最佳时间提前量和最优相关系数,并提出了一个定量的预报模型.模型的输出参量为24 h之后的当地时子夜(23:31 LT—00:30 LT)、清晨(05:31 LT—06:30 LT)、正午(11:31 LT—12:30 LT)、傍晚(17:31 LT—18:30 LT)4个特征时间段相对论电子通量1 h平均值,预报的相对论电子通量有>0 6 MeV和>2MeV明个谱段,预报精度0.7左右.这种预报模式对地球同步轨道卫星的自主安全运行具有较好的应用价值.

There is a good correlation between the relativistic electron flux and the P-component （perpendicular to the orbit plane and points northward） of magnetic field at geosynchronous orbit, and more importantly,the later happened 1～2 day earlier than the former.So the relativistic electron flux can be forecasted by the magnetic field measurement onboard.Firstly,the physical mechanisms possibly governing the correlation have been analyzed in this paper.Secondly,by analyzing the data of GOES11（an geosynchronous orbit satellite which longitude is 135°W）,the best advanced time and linear correlation will be found out.Finally,a quantitative prediction model is developed.The outputs are hourly-averaged flux on four typical time periods 24 hours later.These four typical time periods are：midnight（23：31 LT—00：30LT）,morning（05：31 LT—06：30LT）,noon（11：31 LT—12：30 LT）,evening（17：31 LT—18：30LT） of local time.The relativistic flux of model has two energy spectrums which are0.6 MeV and2 MeV.The model Prediction Efficiency（PE） is about 0.7. This prediction model is of great application to synchronous satellites.