CCC-0331 EGS4.

EGS4.

The EGS code system is one of a chain of three codes designed to solve the electromagnetic shower problem by Monte Carlo simulation. This chain makes possible simulation of almost any electron-photon transport problem conceivable. The structure of the system, with its global features, modular form, and structured programming, is readily adaptable to virtually any interfacing scheme that is desired on the part of the user.

EGS4 is a package of subroutines plus block data with a flexible user interface. This allows for greater flexibility without requiring the user to be overly familiar with the internal details of the code. Combining this with the macro facility capabilities of the Mortran3 language, this reduces the likelihood that user edits will introduce bugs into the code. EGS4 uses material cross section and branching ratio data created and fit by the companion code, PEGS4.

EGS4 allows for the implementation of importance sampling and other variance reduction techniques such as leading particle biasing, splitting, path length biasing, Russian roulette, etc.

See http://rcwww.kek.jp/research/egs/ for current information on EGS

For EGS-5, please visit http://rcwww.kek.jp/research/egs/egs5.html, and for EGS5 sources see http://rcwww.kek.jp/research/egs/egs5_source/egs5.160113.tar.gz

EGS employs the Monte Carlo method of solution. It allows all of the fundamental processes to be included and arbitrary geometries can be treated also. Other minor processes, such as photoneutron production, can be added as a further generalization. Since showers develop randomly according to the quantum laws of probability, each shower is different. We again are led to the Monte Carlo method.

None noted.

The running time is dependent upon the problem being solved.

DATA LIBRARIES: A variety of automated data sets (18 files) is provided. EGS (Electron-Gamma Shower), based on code development in the early 1960s by H.H. Nagel, represents several years of additional development.

• Richard L. Ford and Walter R. Nelson
  The EGS Code System: Computer Programs for the Monte Carlo Simulation of Electromagnetic Cascade Showers, (Version 3) SLAC-210 (June 1978).

• Hideo Hirayama:
  Revision of the Sternheimer Density Effect Coefficients in PEGS4, KEK Internal 95-17 (November 1995) R

An IBM 3081 or a VAX computer is required for version CCC-0331/01. The PC version runs on a Compaq 80386/20 MHz with 4-5 Mbytes of memory (RAM).

A FORTRAN compiler is required. MORTRAN is a structured programming language that is implemented as a set of macros which are used by a macro- processor to translate the language into ANSI-standard FORTRAN (a preliminary step in the job). The resulting program is then run like any other FORTRAN program. The version /03 runs using the Lahey Fortran Compiler F77L/32/EM and A.I. Architect's operating system OS-386. The NDP Fortran and Pharlap Operating System can be used, but modifications are required. Both of these 32-bit compilers run in protected mode, making use of extended memory to exceed the 640 Kbyte limit of MS-DOS necessary for full support of EGS4; and, therefore, require their respective memory manager operating systems.

Contributed by: Radiation Safety Information Computational Center
                Oak Ridge National Laboratory, Oak Ridge, TN, USA

Developed by: Radiation Physics Group
              Stanford Linear Accelerator Center
              Stanford University, Stanford, CA

              National Laboratory for High Energy Physics (KEK)
              Oho-machi, Tsu-kuba-gun, Ibaraki-ken, Japan

              National Research Council of Canada, Ottawa, Canada

              Institute for Applied Physiology and Medicine, Seattle, WA, USA