1. NAME AND TITLE

ELF: Monte Carlo Neutron Transport Code System for Cylinders and Spheres.

AUXILIARY ROUTINES

LEC-AWRE: Cross Section Handling Code.

ELF-NEUTRON: Monte Carlo Neutron Transport Code.

ELF-VARI-PYRO: Analysis Code.

DATA LIBRARY

UKNLD: Data Library 91 elements.

2. CONTRIBUTOR

Shielding Laboratory, CEA/CEN/Fontenay-aux-Roses Nuclear Research Center, now located at CEA/CEN/Saclay, Gif-sur-Yvette, France.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; IBM 360.

4. NATURE OF PROBLEM SOLVED

ELF was designed to study the propagation of neutrons in cylindrical and spherical geometries using AWRE cross sections. In cylindrical geometry the external contour can be circular or polygonal, the limiting conditions at this contour being a vacuum or total reflection.

5. METHOD OF SOLUTION

The Monte Carlo method is used to compute the radiation transport. Auxiliary routines are used for the preparation of cross sections, the study of variance, and to further analyze the ELF collision results.

ELF-VARI-PYRO calculates the spectrum and detector responses from ELF-NEUTRON collision results. The calculation of the mean value is associated with a statistical error bar and a normality test.

The UK-AWRE data library is updated periodically and the update is available from CCDN, Saclay, France.

6. RESTRICTIONS OR LIMITATIONS

The following limits apply for 265K storage: 10 elements, 20 materials, 30 meshes, 150 energy intervals, 200 neutron emission energies, and 100 points defining the radial distribution.

7. TYPICAL RUNNING TIME

No study has been made by RSIC of typical running times for ELF.

Estimated running time of the sample problem on the IBM 360/91: 5 minutes.

8. COMPUTER HARDWARE REQUIREMENTS

The code system is operable on the IBM 360/75/91 hardware configuration. 256K of core storage is required.

9. COMPUTER SOFTWARE REQUIREMENTS

Standard IBM 360 OS Compilers may be used.

10. REFERENCES

F. Gervaise, "ELF Program-Description of Utilization," CEA-Note N-1361 (ORNL-tr-2409) (1970).

F. Gervaise, "ELF-NEUTRON Program," CEA-Note N-1255 (ORNL-tr-2519) (1970).

K. Parker, "The Aldermaston Nuclear Data Library as at May 1963," AWRE-O-70/63 (September 1963).

D. S. Norton, "The UKAEA Nuclear Data Library," AEEW-M824 (February 1968).

D. S. Norton and J. S. Story, "UKAEA Nuclear Data Library, January 1967," AEEW-M802.

P. J. Hemmings and S. M. Offord, "Photon Interaction Data in the UKAEA Nuclear Data Library," AHSB(S)R 109 (1966).

11. CONTENTS OF CODE PACKAGE

Included are the referenced documents and two (1.2MB) DOS diskettes which contain the source codes, data libraries, and sample problem input and output.

12. DATE OF ABSTRACT

June 1972; reviewed December 1984.