论文标题
使用电离层闪烁的小尺度特征的测量。与折射率测量的比较
A measurement of small-scale features using ionospheric scintillation. Comparison with refractive shift measurements
论文作者
论文摘要
我们提出了一项由中纬度电离层引起的闪烁研究。通过实施行星际闪烁研究当前使用的方法来测量低频下的振幅闪烁，我们证明，可以使用Murchison广场阵列在弱方案中研究电离层闪烁，这对$ \ sim $ \ sim $ \ sim $ \ sim的频率均为$ 300 $ 154 mhz的估计范围（$ 300 mhz）的结构敏感。在最极端的情况下。分析超过1000个单独的2分钟观测值，我们将电离层相位的变异与以前的折射率测量值进行了比较，这对折射率的测量值几乎对尺度最敏感。发现这两个测量值高度相关（皮尔逊相关系数0.71）。我们观察到，对于活跃的电离层，这两个指标之间的关系与300m和2000m相关尺度之间的Kolmogorov湍流描述了电离层的结构是否相符。在最极端的电离层条件下，有时发现折射率低估了四个以上的小差异，而正是这些电离层条件可能会对射电天文学观察产生重大影响。
We present a study of scintillation induced by the mid-latitude ionosphere. By implementing methods currently used in Interplanetary Scintillation studies to measure amplitude scintillation at low frequencies, we have proven it is possible to use the Murchison Widefield Array to study ionospheric scintillation in the weak regime, which is sensitive to structures on scales $\sim$300 m at our observing frequency of 154 MHz, where the phase variance on this scale was 0.06 rad$^{2}$ in the most extreme case observed. Analysing over 1000 individual 2-minute observations, we compared the ionospheric phase variance with that inferred with previous measurements of refractive shifts, which are most sensitive to scales almost an order of magnitude larger. The two measurements were found to be highly correlated (Pearson correlation coefficient 0.71). We observed that for an active ionosphere, the relationship between these two metrics is in line with what would be expected if the ionosphere's structure is described by Kolmogorov turbulence between the relevant scales of 300m and 2000m. In the most extreme ionospheric conditions, the refractive shifts were sometimes found to underestimate the small-scale variance by a factor of four or more, and it is these ionospheric conditions that could have significant effects on radio astronomy observations.
