User's guide to ESME v. 8.1

ESME is a computer program to calculate the evolution of a distribution of particles in energy and azimuth as it is acted upon by the radio frequency system of a proton synchrotron. It provides for the modeling of multiple rf systems, feedback control, space charge, and many of the effects of longitudinal coupling impedance. The capabilities of the program are described, and the requirements for input data are specified in sufficient detail to permit significant calculations by an uninitiated user. The program is currently at version 8.1 and extensively modified since the previous user documentation. Changes since the 7.xx versions include a new command and associated parameters for mapping phase space flow lines, new names for a few parameters, and a few new parameters for old commands. Special attention has been given to features relating to calculation of the collective potential and the generation of phase space trajectories including its effects. The VAX-based code management convention has been modified slightly to permit pre-compile options to be used in the include files as well as the program source files. The biggest change from v. 8.0 to v. 8.1 is the addition of code for HIGZ-based graphics; the new code and that using DI3000/GRAFMAKER are alternatives selectable at compilation. Other changes relate to improved control of smoothing options in the calculation of collective potential, fourier spectra, and mountain range plots