Evolutionary Optimization of a Horn Antenna for the RHINO 21 cm Cosmology Experiment

The Genetically Evolved NEutrino Telescopes for Improved Sensitivity (GENETIS) project explores the optimization of physics detector designs using genetic algorithms (GAs) in high-dimensional parameter spaces. We apply this methodology to the design of a horn antenna for the Remote HI eNvironment Observer (RHINO) experiment, which aims to use a large horn antenna at ~4 m wavelengths to detect the redshifted, sky-averaged 21 cm brightness temperature from neutral hydrogen gas around the first stars and galaxies. We use a GA to evolve the complex geometric parameters of the horn antenna (including waveguide dimensions, wall dimensions and angles, and ridge features) with a science outcome as the sole figure of merit. This initial investigation presents the methodology, optimization landscape, and potential design improvements resulting from the evolutionary process, demonstrating the viability of using evolutionary computation to design antennas that satisfy the stringent demands for spectral smoothness and low environmental sensitivity required for precision global 21 cm radiometry. This work establishes a foundation for continued evolution of optimal designs tailored for high-precision radio astronomy applications.