High time resolution riometer and X-ray measurements of conjugate electron precipitation from the magnetosphere
High time resolution riometer and X-ray measurements of conjugate electron precipitation from the magnetosphere
复制标题
磁层共轭电子沉淀的高时间分辨率测量仪和 X 射线测量
作者：
T. Rosenberg;J. Siren;L. Lanzerotti
在这封信中，我们描述了由在南极洲西普尔站（76 °S; 84 °W; L = 4.2）的测微器记录的宇宙噪声吸收数据与来自加拿大罗伯瓦尔（48.3° N; 72.1° W）附近共轭区的韧致辐射X射线的同时气球测量的比较。宇宙噪声的吸收和X射线的产生都是由磁层中高能电子（E ~ 15 keV）的沉淀引起的。测量的时间分辨率和空间覆盖范围使我们能够第一次显示在电离层共枕点的电子沉淀的快速波动的相似性和一致性。此外，数据表明，快速响应riometers是能够解决的时间尺度上的电子沉淀的时间结构，接近电子微暴流（1秒的顺序）。用于测量沉淀粒子效应的riometers相对简单，为高层大气电离现象的研究开辟了重要的新途径。
In this letter we describe the comparison of cosmic noise absorption data recorded by a riometer at Siple Station, Antarctica (76 °S; 84 °W; L ∼4.2) with simultaneous balloon measurements of bremsstrahlung X rays from the conjugate region near Roberval, Canada (48.3° N; 72.1° W). Both the cosmic noise absorption and the production of X rays are caused by the precipitation of energetic electrons (E ≳ 15 ke V) from the magnetosphere. The time resolution and spatial coverage of the measurements enable us for the first time to show the similarity and simultaneity of rapid fluctuations of electron precipitation at ionospheric conjugate points. Furthermore, the data suggest that fast-response riometers are capable of resolving temporal structures in electron precipitation on a time scale which approaches that of electron microbursts (of the order of 1 s). The relative simplicity of riometers for the measurement of precipitating particle effects opens up important new avenues of research in studies of upper atmosphere ionisation phenoma.