RSIC COMPUTER CODE PSR-013

1. NAME AND TITLE

SUPERTOG: Data Generator--Fine Group Constants and P_N Scattering Matrices from ENDF/B.

AUXILIARY ROUTINES

The DLC-2 RETRIEVAL PROGRAM retrieves SUPERTOG output from a card image tape written in the ANISN card image format. This program will retrieve data from a maximum of 46 data sets and merge this data onto one data set. It will then, by input option, edit the data, punch cards in either the ANISN or DTF-IV format, or write an unformatted tape for use by ANISN. Another program is available which will merge up to a maximum of four card image tapes written in the GAM-II update format onto a single tape. This program can also take the one-dimensional arrays from one tape and the two-dimensional arrays from another tape and merge this information onto a single tape. The single tape is input to the SUPERTOG version of the GAM-II update program. The GAM-II update program has been modified to accept output from SUPERTOG on either punched cards or magnetic tape.

2. CONTRIBUTORS

Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Interuniversity Reactor Institute, Delft, Netherlands, through the OECD NEA Data Bank, Gif-sur-Yvette, France.

3. CODING LANGUAGE AND COMPUTER

Fortran IV; IBM 360 SUPERTOG-IV (A), IBM 360 SUPERTOG-III (B).

4. NATURE OF THE PROBLEM SOLVED

In SUPERTOG-IV the inelastic treatment of some materials was corrected; provision was made for making fission spectra; cross-section arrays were made 5000 elements long, thus permitting the use of ENDF/B-IV format. SUPERTOG-III accepts nuclear data in either a point by point or parametric representation as specified by ENDF/B. This data is averaged over each specified group width. The explicit assumption is made that the flux per unit lethargy is constant or that a suitable weight function will be supplied by the user. When resonance data is available, resolved and unresolved resonance contributions are calculated and used as specified by input options. Fine group constants such as one-dimensional reaction arrays (absorption, fission, etc.), P_n elastic scattering matrices, and inelastic and (n,2n) scattering matrices are generated and placed on tapes in formats suitable for use by GAM-I, GAM-II, ANISN, or DOT.

5. METHOD OF SOLUTION

The single-level Breit-Wigner formalism is used for calculation of cross sections in the resolved resonance region. Cross sections in the unresolved resonance region are computed by taking averages over suitable Porter-Thomas distributions of the neutron and fission widths. Smooth cross sections are calculated by integration of point-cross-section data given in ENDF/B file 3. Elastic scattering matrices are computed from Legendre coefficients of the scattering angular-distribution data. Inelastic scattering and (n,2n) matrices are computed from excitation functions for individual levels and by using a nuclear evaporation model above the region of resolved levels.

6. RESTRICTIONS OR LIMITATIONS

Since fixed, rather than flexible, dimensions are used, it is important to be aware of the maximum values allowed for certain key variables. Examples are: number of groups 150, number of data points for each reaction type 4000, and the number of Legendre coefficients 30.

SUPERTOG-III employs a rather elaborate overlay structure and extensive use of equivalence statements to minimize core requirements.

7. TYPICAL RUNNING TIME

(Times quoted are for the IBM 360/91.) Running time varies greatly and is a function, primarily, of the number of groups, the number of resolved resonances, and the length of the elastic scattering matrix. The average time required to generate DLC-2D from ENDF/B Version III data was 2.2 minutes per nuclide.

Estimated running time of the packaged sample problem for the GAM-II, 99-group structure (239-Pu) MAT:1159 with P-3 elastic scattering is 3.0 minutes.

8. COMPUTER HARDWARE REQUIREMENTS

SUPERTOG-III is designed to operate on IBM 360/50/65/75/91 computers. Approximately 366 K bytes or 94 K words of directly addressable core are required. SUPERTOG-LTT was processed on an IBM 3033 at Oak Ridge National Laboratory.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran IV compiler is required.

10. REFERENCES

R. Q. Wright, "Modifications for SUPERTOG III Mod 2," Informal Notes (April 1978).

R. Q. Wright, "PSR-13/SUPERTOG III Code Package," Mod 1 Informal Notes (July 1973).

R. Q. Wright, N. M. Greene, J. L. Lucius, C. W. Craven, Jr., "SUPERTOG: A Program to Generate Fine Group Constants and Pn Scattering Matrices from ENDF/B," ORNL-TM-2679 (September 1969).

SUPERTOG-II Informal Notes, ORNL.

R. Q. Wright, "Increasing the Number of Groups Allowed in SUPERTOG-II," Informal Notes.

SUPERTOG-III Informal Notes, ORNL (August 1972).

R. Q. Wright, "SLOGAN for SUPERTOG-III," (July 1972).

SAD - Secondary Angular Distributions Informal Notes (1968).

R. F. Berland, "CHAD-Code to Handle Angular Data," NAA-SR-11231 (December 1965).

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

September 1972; updated October 1983, August 1985, April 1990, January 1992.