On the design of an isochronous cyclotron meson factory

Abstract

A fixed energy high beam intensity isochronous cyclotron for meson production is under consideration at CERN, Geneva. A convenient and rapid method is described for determining suitable spiral ridge fields giving a chosen variation of the linearized vertical betatron oscillation frequency versus energy. The method implies an approximation of the field ridges into a prechosen number of small hard-edged steps. Some computational results are discussed and a preliminary choice of machine parameters given, as well as a conceptional design of the field magnet and the general layout of other major machine components. The problem of shielding is discussed. A series of shielding studies involving experiments carried out at 400 MeV on the CERN Synchro-Cyclotron are described and some results are quoted. Finally, a description is given of a series of irradiation and activation experiments involving samples of various materials placed inside the CERN SC.