The Distribution Of Radio Brightness Over The Solar Disk At A Wavelength Of 21 Centimetres. I. A New Highly Directional Aerial System

Abstract

A new aerial system of very high resolving power has been designed for use in determining the distribution of radio brightness across the solar disk at a wavelength of 21 cm. Thirty-two aerials with paraboloidal reflectors are evenly spaced in an east-west direction over a distance of about 700 ft., and are connected by a branching system of balanced open-wire transmission lines to a receiver. The aerial system produces multiple beams each 3' of arc wide and spaced 1.7° apart. The rotation of the Earth causes one after another of the aerial beams to scan the disk of the Sun. The record obtained from the radio receiver gives a one-dimensional brightness distribution over the solar disk.