RSIC COMPUTER CODE PSR-098

1. NAME AND TITLE

GALAXY-6: Neutron Multigroup Cross Section Processor.

2. CONTRIBUTOR

OECD NEA Computer Programme Library, Ispra, Italy.

3. CODING LANGUAGE AND COMPUTER

Fortran IV and Assembler Language; IBM 370.

4. NATURE OF PROBLEM SOLVED

GALAXY-6 calculates spectrum-weighted group-averaged nuclear cross sections and group-to-group transfer cross sections from the evaluated microscopic cross section data contained in the UKAEA Nuclear Data Library.

5. METHOD OF SOLUTION

Standard numerical integration methods are used by GALAXY-6. If the reciprocal of the total cross-section of the mixture is needed for spectrum-weighting purposes, it is calculated at each of the aggregate of energy points at which the cross-sections of the constituent material are given. Several energy group dependent quantities are then computed which are the same for every reaction and material. If the reciprocally averaged transport cross-section for the mixture is needed, it is computed for each specified energy group from the total cross-section data, the elastic cross-section data, and the elastic angular distribution data for the constituent materials of the mixture. GALAXY-6 then computes group-averaged, spectrum-weighted cross sections for specified reactions and energy groups with group-to-group transfer cross-sections for appropriate reactions for all or a specified subset of the constituent materials of the mixture. The results of these computations, together with other data and some of the input control information supplied by the user, are written on a tape. The entire process is repeated for each remaining mixture specified in the control input data.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

No study has been made by RSIC of typical running times for GALAXY-6.

8. COMPUTER HARDWARE REQUIREMENTS

GALAXY-6 is operable on the IBM 370 computers. It uses a maximum of three discs and three tapes.

9. COMPUTER SOFTWARE REQUIREMENTS

Fortran IV and Assembler Language compilers are required.

10. REFERENCE

J. A. Price, "A Guide to GALAXY 6 Part 1," AWRE 013/75 (November 1975).

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 and output.

12. DATE OF ABSTRACT

March 1984.