Radio antenna design for sky-averaged 21 cm cosmology experiments: the REACH case

Understand

Following the reported detection of an absorption profile associated with the 21~cm 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 21~cm 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 modelling and characterization of the instrumentation.
• There is detailed the quantitative figures of merit and numerical modelling used to assist the design process of the REACH dipole antenna (one of the 2 antenna designs for REACH Phase I).