磁声波，即离子伯恩斯坦波，在内磁层动力学及其演化中具有重要的作用。随着范阿伦卫星及ERG卫星发射，磁声波成为当今空间物理的研究热点。但磁声波在实际观测中缺乏定量的标定，同时其空间分布也缺乏基于观测的经验模式。本项目以磁声波识别的定量标准、磁声波特征参量在内磁层不同区域的分布特征、内磁层磁声波特征参量随太阳风动压及地磁活动指数之间关系为主要的研究内容。通过范阿伦卫星的EMFISIS探测的波动强度、传播角、极化参量及平面度参量的数值统计分布特征，获得磁声波识别的定量标准。在此基础上，通过磁声波的统计分析， 获得磁声波的幅度及频率在内磁层不同区域的分布特征。最后结合太阳风及地磁活动指数的观测，建立不同的太阳风动压及地磁条件下的磁声波的幅度及频率的经验模型。研究结果将对揭示磁声波在内磁层中的演化过程，建立内磁层预报的动态模型具有重要意义。

Fast magnetosonic (MS) waves, also named as ion Bernstein modes, can play an important role in the dynamics and evolution of the inner magnetosphere. After the Van Allen probe and ERG mission are successfully launched, the MS wave has become a research hot spot. However, it is an unsolved problem how to quantitatively identify MS waves. The experimental model of the spatial distribution for MS waves has not been built. This project focuses on the research of quantitative identification of MS waves, the spatial distribution of MS wave characteristic, and the relationship between the solar wind dynamic pressure, geomagnetic activity index and spatial distribution of MS wave characteristic. Based on observations of the EMFISIS instrument on the Van Allen probe, through the value distribution of the parameters (including the strength, wave normal angle, wave ellipticity, the degree of polarization) for MS waves, the project plans to obtain the quantitative criterion for identify MS waves. Through statistical analysis of the MS events, the spatial distribution of the frequency and strength for MS waves will be obtained. Thereafter, the experimental model will be built for the spatial distribution of the frequency and strength for MS waves in different the solar wind dynamic pressure and geomagnetic activity. The result of the project is expected to reveal the dynamics and evolution of the inner magnetosphere and be great helpful to build the dynamical model of the inner magnetosphere.