Based on the results of the experiments performed in 2005–2010 within the framework of the Sura—DEMETER program, we analyze the features of the precipitations of energetic electrons (with energies E ≈ 100 keV) from the Earth’s radiation belt. The modification of the ionospheric F 2 region was conducted by means of high-power HF O-mode radio waves radiated in the CW regime. The precipitations were detected using the equipment onboard DEMETER, a French microsatellite. The conditions of precipitation appearance were determined, and it was found that the electron precipitation region was stretched along the geomagnetic meridian to a distance of 1300 km; the size of the region in the transverse direction is about 400 km. It was shown by ionosonde measurements that such precipitations lead to increased absorption of radio waves in the lower ionosphere. It is assumed that the mechanism for precipitation of electrons from the Earth’s radiation belt is determined by the interaction of energetic electrons with VLF radio waves, which are generated due to the interaction of the amplitude-unmodulated O-mode pump wave with the ionospheric plasma near the wave reflection height.

中文翻译：

---

高功率高频无线电波刺激地球辐射带高能电子的沉淀，用于修改中纬度电离层

基于2005-2010年在Sura-DEMETER计划框架内进行的实验结果，我们分析了来自地球辐射带的高能电子（能量E≈100 keV）的沉淀特征。电离层 F 2 区域的修改是通过在 CW 范围内辐射的高功率 HF O 模式无线电波进行的。使用法国微型卫星 DEMETER 上的设备检测到降水。确定了降水出现的条件，发现电子降水区沿地磁子午线延伸至1300公里；该区域的横向面积约为 400 公里。电离探测器测量表明，这种降水会导致电离层低层对无线电波的吸收增加。