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arXiv · 2305.11479

A new technique to measure noise parameters for global 21-cm experiments

Danny C. Price·Cheuk-Yu Edward Tong·Adrian T. Sutinjo·Nipanjana Patra·Lincoln J. Greenhill
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Abstract

Radiometer experiments to detect 21-cm Hydrogen line emission from the Cosmic Dawn and Epoch of Reionization rely upon precise absolute calibration. During calibration, noise generated by amplifiers within the radiometer receiver must be accounted for; however, it is difficult to measure as the noise power varies with source impedance. In this letter, we introduce a convenient method to measure the noise parameters of a receiver system, which is practical for low-frequency receivers used in global 21-cm experiments.

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Danny C. Price, Cheuk-Yu Edward Tong, Adrian T. Sutinjo, Nipanjana Patra, Lincoln J. Greenhill. 2023-05-19. A new technique to measure noise parameters for global 21-cm experiments. https://arxiv.org/abs/2305.11479

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