1. NAME AND TITLE

GECINX: A Code System for Collapsing Multigroup Cross Sections in CCCC Format.

2. CONTRIBUTOR

General Electric Company, Sunnyvale, California.

3. CODING LANGUAGE AND COMPUTER

Fortran IV; Honeywell 6000.

4. NATURE OF PROBLEM SOLVED

GECINX is a major revision of the computer code CINX which is designed to collapse multigroup cross sections to a subset of the original group structure. The input and output cross sections are in the Committee for Computer Code Coordination (CCCC) Version IV formats for files ISOTXS, BRKOXS and DLAYXS.

5. METHOD OF SOLUTION

The weighting function used for the collapse of the cross section may be generated by the code, using a thermal spectrum at low energies, a 1/E spectrum at midrange energies, and a Watt fission spectrum at high energies. Alternatively, one or more weighting spectra may be input by the user. If the weighting spectrum specified is the same as the one used to generate the original multigroup cross sections, then the resulting collapse cross sections will be essentially the same as those which would be obtained by generating the few-group cross sections directly.

6. RESTRICTIONS OR LIMITATIONS

Variable dimensioning is used throughout the program, thereby eliminating any restrictions imposed by number of energy groups, number of temperatures, etc.

7. TYPICAL RUNNING TIME

The test problem collapsed two materials from 50 to 4 energy groups for all three input file types. It required 30 seconds of computer processor time.

8. COMPUTER HARDWARE REQUIREMENTS

GECINX is operable on the Honeywell 6000.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran IV compiler is required.

10. REFERENCES

a. Included in documentation:

R. Protsik, "GECINX - Revised User's Guide," Informal Notes (February 1982).

R. Protsik, "GECINX: A Computer Code for Collapsing Multigroup Cross Sections in CCCC Format," GEFR-00499, UC-79E (November 1979).

b. Background Information:

R. B. Kidman and R. E. MacFarlane, "CINX: Collapsed Interpretation of Nuclear X-Sections," LA-6287 (April 1976).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document (10.a) and one (1.2MB) DOS diskette which contains the source code and sample problem input and output.

12. DATE OF ABSTRACT

January 1983; revised October 1983, August 1984.