资源环境科技发展态势分析平台

Magnetosonic (MS) waves are electromagnetic waves that play important roles in the acceleration and scattering of radiation belt electrons. However, previous statistical analyses of the global MS wave distribution were mainly restricted to magnetic field measurements. In this study, we first report a low‐harmonic MS wave event observed only by the electric field instrument of Van Allen Probes. The MS wave frequencies follow the local proton gyrofrequency (f_cp), which suggests the characteristics of nearly local generation. We further statistically investigate similar wave events using Van Allen Probes data. The identified MS wave power exhibits peaks between 4f_cp and 10f_cp, regardless of the L‐shell, but it shows a magnetic local time (MLT) dependence. This work is supplemental to previous MS wave frequency spectra and provides new insights to better understand the source region of MS waves in the Earth’s magnetosphere.