Radio Antenna Design for Sky-Averaged 21cm Cosmology Experiments: The REACH Case
Radio Antenna Design for Sky-Averaged 21cm Cosmology Experiments: The REACH Case
复制标题
天平均 21 厘米宇宙学实验的无线电天线设计：REACH 案例
DOI：
10.1142/s2251171722500015
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发表时间：
2022
影响因子：
1.3
通讯作者：
Cumner J
中科院分区：
文献类型：
--
作者：
Cumner J
继 2018 年 EDGES 实验报告检测到与来自宇宙黎明的 21 厘米天空平均信号相关的吸收剖面后，已经开展了许多实验来验证这一结果。本文讨论了全球 21 厘米实验的设计过程，特别关注宇宙氢分析无线电实验 (REACH)。该实验将寻求使用仪器的详细建模和表征来理解和补偿存在的系统误差。详细的定量品质因数和数值建模用于协助 REACH 偶极天线（REACH 第一阶段的两种天线设计之一）的设计过程。该设计过程产生了 2.5:1 频率带宽偶极子。该设计的目的是平衡频谱平滑度和低阻抗反射，并能够描述和理解天线对天空信号的响应，以便在观测和数据分析期间为至关重要的校准提供信息。
Following the reported detection of an absorption profile associated with the 21cm sky-averaged signal from the Cosmic Dawn by the EDGES experiment in 2018, a number of experiments have been set up to verify this result. This paper discusses the design process used for global 21cm experiments, focusing specifically on the Radio Experiment for the Analysis of Cosmic Hydrogen (REACH). This experiment will seek to understand and compensate for systematic errors present using detailed modeling and characterization of the instrumentation. Detailed quantitative figures of merit and numerical modeling are used to assist the design process of the REACH dipole antenna (one of the two antenna designs for REACH Phase I). This design process produced a 2.5:1 frequency bandwidth dipole. The aim of this design was to balance spectral smoothness and low impedance reflections with the ability to describe and understand the antenna response to the sky signal to inform the critically important calibration during observation and data analysis.