Classical Cyclotron

This chapter introduces the classical cyclotron,Cyclotron classical and the theoretical material needed for the simulation exercises. It begins with a brief reminder of the historical context, and continues with beam optics and with the principles and methods which the classical cyclotron leans on, including The simulation of a cyclotron dipole will either resort to an analytical model of the field: the optical element DIPOLE, or will resort to using a field map together with the keyword TOSCA to handle it and raytrace through. An additional accelerator device needed in the exercises, CAVITE, simulates a local oscillating voltage. Running a simulation generates a variety of output files, including the execution listing zgoubi.res, always, and other zgoubi.plt, zgoubi.CAVITE.out, zgoubi.MATRIX.out, etc., aimed at looking up program execution, storing data for post-treatment, producing graphs, etc. Additional keywords are introduced as needed, such as the matching procedure FIT[2]; FAISCEAU and FAISTORE which log local particle data in zgoubi.res or in a user defined ancillary file; MARKER; the “system call” command SYSTEM; REBELOTE, a ‘do loop’; and some more. This chapter introduces in addition to spin motion in accelerator magnets; dedicated simulation exercises include a variety of keywords: SPNTRK, a request for spin tracking, SPNPRT or FAISTORE, to log spin vector components in respectively zgoubi.res or some ancillary file, and the “IL = 2” flag to log stepwise particle data, including spin vector, in zgoubi.plt file. Simulations include deriving transport matrices, beam matrix, optical functions and their transport, from rays, using MATRIX and TWISS keywords.