Introduction

The present guide corresponds to the program version dated JUNE 01 1993.

The program DIMAD studies particle behaviour in circular machines and in beam lines.

The trajectories of the particles are computed according to the second order matrix formalism[1]. It does not provide synchrotron motion analysis but can simulate it. The program provides the user with the possibility of defining arbitrary elements to tailor the program to specific uses. The present version of DIMAD is not fully debugged. Please inform one of the following persons about any anomalies observed:

 David Douglas at CEBAF 804/249 7512 


Roger Servranckx at Gabriola 604/247-9567

DIMAD,like its predecessor DIMAT, is the result of many years of experimenting with several different charged particle computer codes.

In 1970 the first author had the good fortune of discovering the program OSECO (Optique du SECond Ordre) written by J.L.LACLARE at SACLAY. Basically OSECO was a second order Tracking program. It was based on the second order matrix formalism of TRANSPORT and was originally written for a CDC computer. Its usefulness in the simulation of the extraction procedure of the Beam Stretcher ALIS and later of EROS led to the desire for a program that would have more analysis power. The first attempt to develop a new program resulted in the program DEPART which was written as a pure differential equation ray tracing program but it soon became clear that DEPART was very awkward to use because of the cumbersome way in which bending magnets were defined in the code. An evolutionary process then took place over a period of several years finally resulting in the present program called DIMAD. Many people contributed in various ways to the development of DIMAT. Dr Leon Katz, while he was Director of the Linear Accelerator Laboratory at Saskatoon, provided strong support for the work. Sheila Flory, Dean Jones, Edward Pokraka, Jim Morrison, and Jean Mary Miketinac provided programming support at different times during the initial program development. Ideas were borrowed freely from the program OSECO and Jean Louis Laclare helped formulate some of the early developments. Karl L Brown of SLAC became influential during the later development phases. He helped formulate the more recent contributions to the program (geometric aberrations, linear analysis of motion around arbitrary reference orbits, and magnet misalignment simulations). It is for these reasons that he has become a coauthor of the present manual.

The authors wish to thank the many DIMAT users of other laboratories for their comments and assistance in locating the many programming errors that have occurred during the evolution of DIMAD.

In 1984, it became clear that tracking codes should operate in a canonical environment ,should provide options for symplectic tracking and should conform to the input STANDARD [2] [3]. Adapting the input code of MAD [4], Lindsay Schachinger transformed the program so it would enjoy a common input with MAD, thereby conforming to the input STANDARD.

With ideas developed originally by E.Forest[5], David Douglas introduced the symplectic tracking options and the canonical variables.

The following persons, listed in alphabetical order, were actively involved in the development of DIMAD :

Karl.L.BROWN (Stanford Linear Accelerator Center)

David DOUGLAS (Continuous Electron Beam Facility)

Lindsay SCHACHINGER (Superconducting Super Collider)

Roger V. SERVRANCKX (University of Saskatchewan)

Uli WIENANDS (TRIUMF Vancouver)

The affiliation listed is the one when most of the contribution occured.