1. NAME AND TITLE

ELGATL: Calculation of Energy Spectra from Coupled Electron-Photon Slowing Down.

2. CONTRIBUTOR

U.S. Department of Energy Environmental Measurements Laboratory, New York, New York.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; CDC-6600.

4. NATURE OF PROBLEM SOLVED

ELGATL calculates electron and photon track lengths in uniform homogeneous media accounting for all major physical particle interactions. It was designed for problems where only energy spectra and not position and direction of particles are required or where source is uniformly distributed.

5. METHOD OF SOLUTION

ELGATL incorporates the direct numerical integration of coupled electron-photon track length equations using iterative techniques.

6. RESTRICTIONS OR LIMITATIONS

ELGATL is valid for energies ranging from 10 keV to over 10 GeV.

7. TYPICAL RUNNING TIME

Typical running time is approximately 10 minutes on the CDC-6600 for 500 energy groups, but it is highly dependent upon the number of groups due to the iterative numerical technique.

8. COMPUTER HARDWARE REQUIREMENTS

A CDC-6600 computer is required.

9. COMPUTER SOFTWARE REQUIREMENTS

A FORTRAN IV compiler is required.

10. REFERENCE

H. L. Beck, "Energy Spectra from Coupled Electron-Photon Slowing Down," HASL-309 (August 1976).

11. CONTENTS OF CODE PACKAGE

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

12. DATE OF ABSTRACT

December 1981.