Synchrocyclotron

This chapter introduces the concept of phase focusing by synchronous acceleration, and the synchrocyclotron which confirmed the principle. Synchrocyclotron style of acceleration in a fixed field alternating gradient accelerator (FFAG) is also addressed. The theoretical material needed for the simulation exercises is essentially that of the Weak Focusing Synchrotron, Chap.  8 , regarding phase stability, and that of the Classical Cyclotron, Chap.  3 , or FFAG optics, Chap.  10 , regarding transverse stability. The chapter begins with a brief reminder of the historical context, and continues with the theoretical material which the synchrocyclotron optics and acceleration techniques lean on. The simulation of a synchrocyclotron is achieved using just three keywords: DIPOLE for the magnet, and CAVITE and SCALING for acceleration. FFAG dipoles have their specific keywords, FFAG and FFAG-SPI (Chap.  10 ). Particle monitoring uses FAISCEAU, FAISTORE, and some others. Optics matching and optimization, and the design of RF programs as well, use FIT[2]. INCLUDE is resorted to, although there is no obligation, in order mostly to simplify the input data files. SYSTEM calls to gnuplot scripts allow ending simulations with various graphs; gnuplot reads data from output files such as zgoubi.fai (produced by FAISTORE), zgoubi.plt (resulting from IL \(=\) 2) and from files zgoubi.*.out resulting from a PRINT command.