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Updated: Jun 30, 2025

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Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
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黑暗时代的模式 21厘米的场所可以通过月球无线电干扰仪访问
Philip Bull1,2, Caroline Guandalin3, Chris Addis3
1Jodrell Bank Centre for Astrophysics, University of Manchester, Manchester M13 9PL, UK.
概括
未来的月球无线电阵列可以通过观察中性的21厘米线来探测早期宇宙. 这些数组显示了检测原始非高斯性,早期宇宙模型的一个关键指标的希望.
科学领域:
- 宇宙学的宇宙学是什么?
- 无线电天文学 无线电天文学
- 天体物理学 天体物理学
背景情况:
- 从中性的21厘米线是3D物质分布在高红移的关键探测器.
- 月球的背面提供了一个无线电安静的环境,非常适合低频无线电天文学.
- 地球的射频干扰和地球的电离层阻碍了低频观测.
研究的目的:
- 预测月球无线电阵列对21厘米双光谱的灵敏度.
- 评估使用月球阵列探测原始非高斯性能的潜力.
- 评估仪器限制和前景移除对灵敏度的影响.
主要方法:
- 模拟低频月球无线电阵列对21厘米双光谱的灵敏度.
- 由于仪器效应和系统学,对里埃空间限制的计算.
- 对局部类型非高斯度的参数化和预测灵敏度 (f_NL).
主要成果:
- 在乐观,样本变异有限的条件下,月球阵列可以实现f_NL ~ 10的宽红移容器.
- 除了前景区域外,对f_NL的敏感性降低了2至0.7.
- 灵敏度取决于红移容器和前景移除的有效性.
结论:
- 月球远端无线电阵列对检测原始非高斯性有希望.
- 有效的前景移除对于实现高灵敏度至关重要.
- 这些阵列可以显著提升我们对早期宇宙宇宙学的理解.
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