资源环境科技发展态势分析平台

We perform a statistical analysis of magnetosonic waves in the slot region based on Van Allen Probes observations from September 2012 to February 2018. Our results demonstrate that the wave occurrence rate increases with enhanced geomagnetic activity and decreasing magnetic latitude, with the presence of strongest slot region magnetosonic waves near the geomagnetic equator within the 08-20 MLT sector. Power spectral densities of slot region magnetosonic waves also intensify during geomagnetically active times, with the occurrence of the major wave power (＞∼10^-5nT²/Hz) below ∼25f_cp (where f_cp is the proton gyrofrequency) and the peak wave intensity (∼10^-3nT²/Hz) below ∼5f_cp at L＞∼2.6. A remarkable gap in the magnetosonic wave frequency spectrum is also revealed at < ∼15f_cp during weak substorm activities (AE 300nT).