论文标题
量化电离层对全局21厘米观测的影响
Quantifying Ionospheric Effects on Global 21-cm Observations
论文作者
论文摘要
我们通过具有时间差异的简化空间模型对地球电离层的两个主要层进行建模，以研究色层对全局21-CM观测值的影响。从分析中，我们发现，由于电离层折射和吸收引起的电离层破坏的大小可能大于预期的全局21-CM信号，并且其大小的变化可能会有所不同，具体取决于电离层条件。在模型中采用的参数空间内，整体21-CM信号的形状在通过电离层传播后会扭曲，而其幅度则弱化。据观察，电离层效应不会随着时间的流逝而取消，因此应在每个时间步长的前景校准中考虑到电离层引入的色度。
We modelled the two major layer of Earth's ionosphere, the F-layer and the D-layer, by a simplified spatial model with temporal variance to study the chromatic ionospheric effects on global 21-cm observations. From the analyses, we found that the magnitude of the ionospheric disruptions due to ionospheric refraction and absorption can be greater than the expected global 21-cm signal, and the variation of its magnitude can differ, depending on the ionospheric conditions. Within the parameter space adopted in the model, the shape of the global 21-cm signal is distorted after propagating through the ionosphere, while its amplitude is weakened. It is observed that the ionospheric effects do not cancel out over time, and thus should be accounted for in the foreground calibration at each timestep to account for the chromaticity introduced by the ionosphere.
