1. NAME AND TITLE

ERPEX: Monte Carlo Distributions of Energetic Proton Ranges in Silicon.

ERPEX represents an extension of CCC-228/SPAR for the silicon study.

2. CONTRIBUTOR

University of Warsaw, Warsaw, Poland.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; CDC CYBER 73-16.

4. NATURE OF PROBLEM SOLVED

The projected range distributions of energetic protons non-channelled in silicon, and relative to radiation damage, are treated. Protons in the range of 0.5 to 2.5 MeV are simulated.

5. METHOD OF SOLUTION

Monte Carlo simulation is used using the computational methods of Berger, and the following assumptions are involved:

1. The total pathlength traversed by the particle in the solid is given before the history of the particle is terminated.

2. The solid has a random or amorphous structure.

3. Multiple-scattering polar deflections are calculated by a simple analytical compression.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

No study has been made by RSIC of typical running time for ERPEX.

8. COMPUTER HARDWARE REQUIREMENTS

ERPEX was designed for the CDC CYBER 73-16 computer.

9. COMPUTER SOFTWARE REQUIREMENTS

A FORTRAN IV compiler is required.

10. REFERENCES

a. Included in the documentation:

J. Tatarkiewicz, "Distributions of Energetic Proton Ranges in Silicon as Determined by the Monte Carlo Method."

T. W. Armstrong and K. C. Chandler, "Informal Memo on Modifications to the SPAR Code," (1974).

T. W. Armstrong and K. C. Chandler, "Stopping Powers and Ranges for Muons, Charged Pions, Protons, and Heavy Ions," Nucl. Instr. Meth. 113 (1975), 313-314.

T. W. Armstrong and K. D. Chandler, "SPAR, A FORTRAN Program for Computing Stopping Powers and Ranges for Mons, Charged Pions, Protons, and Heavy Ions," ORNL-4869 (May 1973).

b. Background information:

M. J. Berger, "Methods in Computational Physics," Vol. 1, 135 (1963).

11. CONTENTS OF CODE PACKAGE

Included are the referenced documents and one (1.2MB) DOS diskette which contains the source code and sample problem input.

12. DATE OF ABSTRACT

August 1977; revised March 1982.