基于范艾伦卫星观测下太阳风动压对嘶声波分布的影响  

Influence of Solar Wind Dynamic Pressure on Hiss Distribution Based on Van Allen Probe Observations

作　　者：袁安 李海梦 唐荣欣 欧阳志海 熊鹰[2] 周猛[1,2] 冯泊溥 邹文倩 邓晓华[2] YUAN An;LI Haimeng;TANG Rongxin;OUYANG Zhihai;XIONG Ying;ZHOU Meng;FENG Bopu;ZOU Wenqian;DENG Xiaohua(School of Physics and Materials,Nanchang University,Nanchang 330031;Institute of Space Science and Technology,Nanchang University,Nanchang 330031)

机构地区：[1]南昌大学物理与材料学院,南昌330031 [2]南昌大学空间科学与技术研究院,南昌330031

出　　处：《空间科学学报》2024年第6期988-997,共10页Chinese Journal of Space Science

基　　金：国家自然科学基金项目资助(42374201,42064009,42304179)。

摘　　要：哨声波作为常见的等离子体波动,对于磁层内能量电子的加速和损失起着重要作用.已有统计研究表明,地磁活动对哨声波的分布具有显著影响,但是关于太阳风活动对其的影响多以事件报道为主.本文使用范艾伦卫星5年的数据进行统计,在排除亚暴注入的影响之后,对等离子体层内嘶声在不同太阳风动压下的分布进行研究.结果表明随着太阳风动压的增强,30~200 Hz和200~500 Hz的嘶声振幅出现了减弱,与太阳风动压的变化呈负相关.与频率较低的嘶声相反,500~1000 Hz以及1000~2500 Hz的嘶声振幅与太阳风动压的变化则是呈现正相关的趋势.此外,嘶声在磁纬上的分布没有明显的峰值,这表明观测到的嘶声大部分都不是本地激发的.而不同频段的嘶声对于太阳风动压的不同响应则可能是由于源区在太阳风动压增强时受到不同程度的影响所导致的.研究嘶声对于太阳风变化的响应情况,对于理解嘶声的起源与演化具有重要作用.As a common plasma waves,whistler mode waves play a crucial role in the acceleration and scattering of energetic electrons in the magnetosphere.Numerous previous statistical studies have demonstrated that geomagnetic activities have a significant impact on the distribution of whistler waves.However,reports on the influence of solar wind activities on them are predominantly event-based.Five years of data from the Van Allen Probes were used for statistical analysis.After excluding the influence of substorm injections,the distribution of plasmaspheric hiss under different solar wind dynamic pres-sures were investigated.The results indicate that as the solar wind dynamic pressure intensifies,the am-plitudes of hiss waves at 30~200 and 200~500 Hz exhibit a weakening trend and show a negative corre-lation with the change in solar wind dynamic pressure.In contrast to low frequency hiss,for hiss at 500~1000 Hz and 1000~2500 Hz,their amplitudes show a positive correlation trend with the change of solar wind.Additionally,there is no distinct peak in the distribution of hiss at magnetic latitudes,sug-gesting that most of the observed hiss is not locally excited.The different responses of hiss in different frequency bands to the solar wind dynamic pressure may be attributed to the fact that the source region is affected to varying degrees when the solar wind dynamic pressure increases.Studying the response of hiss to changes in the solar wind plays an important role in understanding the origin and evolution of hiss.

关 键 词：空间等离子体 等离子体层内嘶声 太阳风动压 磁纬度 

分 类 号：P354[天文地球—空间物理学]