Large Acceptance Magnetic Focussing Horns for Production of a High Intensity Narrow Band Neutrino Beam at the AGS

A set of two large acceptance (20 to 140 mrad) horns have been designed and built to form a parallel beam of 3 GeV/c pions and kaons for the production of an intense, dichromatic neutrino beam. A set of beam plugs and collimators determined the momentum of the particles which pass through the horns. The cooling and maintenance of the horns and target was a particular concern since they were operated with an incident intensity of over 1013 proton/sec. These systems were designed for simplicity, reliability, and easy replacement.