Receiver design for the REACH global 21-cm signal experiment

Journal article

We detail the REACH radiometric system designed to enable measurements of the 21-cm neutral hydrogen line. Included is the radiometer architecture and end-to-end system simulations as well as a discussion of the challenges intrinsic to highly-calibratable system development. Following this, we share laboratory results based on the calculation of noise wave parameters utilising an over-constrained least squares approach. For five hours of integration on a custom-made source with comparable impedance to that of the antenna used in the field, we demonstrate a calibration RMSE of 80 mK. This paper therefore documents the state of the calibrator and data analysis in December 2022 in Cambridge before shipping to South Africa.

Authors: Roque, ILV; Razavi-Ghods, N; Carey, SH; Ely, JA; Handley, W

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Experimental Astronomy
• Volume: 59
• Issue: 1
• Article number: 7
• Publication date: 2025-01-17
• Acceptance date: 2024-12-18
• DOI: 10.1007/s10686-024-09975-3
• EISSN: 1572-9508
• ISSN: 0922-6435
• Language: English
• Keywords: Reionisation; Dark ages; Instrumentation; Calibration; Radiometer; Cosmology