电离层中性气体释放的早期试验效应研究  

Early time effects produced by neutral gas ionospheric chemical release

作　　者：赵海生[1] 徐朝辉 高敬帆 许正文[1] 吴健[1] 冯杰[1] 徐彬[1] 薛昆[1] 李辉[1] 马征征[1] 

机构地区：[1]中国电波传播研究所,电波环境特性及模化技术重点实验室,青岛266107 [2]西安电子科技大学物理与光电工程学院,西安710071

出　　处：《物理学报》2018年第1期292-301,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号：11672068,61601419)资助的课题

摘　　要：在电离层释放电子吸附类中性气体能够引起电离层电子密度耗空,在释放之后快速形成"电离层洞";同时,由于释放气体的快速膨胀,挤压背景等离子体,在电离层洞的外边缘产生"壳状"电子密度增强结构,电离层洞和电子密度增强结构同时存在是释放早期试验效应的显著特征.本文研究了电离层中性气体释放的早期试验效应,建立了释放早期电子密度的时空演化物理模型,仿真了释放早期电子密度的时空演化过程,同时采用射线追踪方法研究了释放后10 s和120 s不同频率信号在扰动区的传播效应,并反演得到了电离层垂直探测电离图,反演结果与一次火箭喷焰的实际观测结果吻合较好,初步验证了本模型的正确性.The artificial release of electron adsorbing material can cause electron density to be depleted in the ionosphere,forming the ＂ionospheric holes＂ rapidly. At the same time, the ＂shell＂ structure of the electron density enhancement around the hole is produced, owing to the extrusion of background plasma caused by rapid expansion of the release.The coexistence of ionospheric hole and enhancement structure is the significant characteristics of the early time effects.In this paper, the early time effects of neutral chemicals released into ionosphere are studied, and a physical model of spatiotemporal evolution about early time electron density is set up. At t = 1 s, the maximum electron density in the enhanced region is 2.46 × 10-6 cm-（-3）, approximately 2.8 times as great as background electron density, then the electron density at the boundary gradually decreases. At t = 30 s, the maximum electron density is 1.58 × 10-6 cm-（-3）, which is about 1.7 times the background electron density. At t = 120 s the maximum electron density in the enhanced region is1.12 × 10-6 cm-（-3）, which is 1.2 times the background electron density. Within 120 s after release, the size of the ionospheric cavity increases gradually; at t = 5 s the distribution range of the released chemical material is of a sphere of about10 km in diameter; at t = 120 s the distribution diameter of the released chemical material is more than 70 km, and at the same time, the depletion depth of the ionospheric hole decreases slowly. At t = 1 s, the depletion depth of the ionospheric hole is about 100%, and at t = 120 s the depletion depth of the ionospheric cavity decreases to 95%. The effects of different-frequency radio waves propagating through ionospheric disturbance at t = 10 s and t = 120 s are simulated by the ray tracing. At t = 10 s, the effect of electron density enhancement is remarkable, and the thickness of the enhancement is about 10 km, and the electronic density enhancement area can reflect the radio wave signal at a frequ

关 键 词：电离层 化学物质释放 六氟化硫 早期效应 

分 类 号：P352[天文地球—空间物理学]