1. NAME AND TITLE

GMA: Generalized Least-Squares Evaluation of Related Cross Sections for ENDF/B Based on Gauss, Markov, and Aitken.

AUXILIARY:

RCL: Editing and listing of the data file GMDATA.CRD.

DAT: Reduction of the data file GMDATA.CRD to the input data file for GMA: data.gma.

2. CONTRIBUTOR

Argonne National Laboratory - West, Idaho Falls, Idaho.

3. CODING LANGUAGE AND COMPUTER

Fortran 77, Fortran 90; Pentium based PC, IBM RS/6000 and Sun workstations.

4. NATURE OF PROBLEM SOLVED

The simultaneous evaluation of the cross sections of ⁶Li(n,), ⁶Li(n,n), ¹⁰B(n,₀), ¹⁰B(n,₁), ¹⁰B(n,n), ¹⁹⁷Au(n,), ²³⁸U(n,), ²³⁵U(n,f), ²³⁹Pu(n,f) ²³⁸U(n,f), and the thermal constants was part of the evaluation of these data for ENDF/B-VI. The FORTRAN codes and the data files used for the simultaneous evaluation are known as GMA. Corrections for some data reported in the literature and the addition of several new data sets results in negligible changes except for the fission cross sections where minor changes occur relative to the evaluation for ENDF/B-VI. The Fortran codes and the data files used for the simultaneous evaluation are included in this package.

5. METHOD OF SOLUTION

GMA utilizes the method of generalized least-squares estimation. Associated codes included are RCL (which is used to edit, list and expand the basic data file) and DAT (which is used to reduce the cross section data to a common energy grid).

6. RESTRICTIONS OR LIMITATIONS

Interpolation, extrapolation, labeling, and markers are used which restrict the application to the cross sections listed under number four above.

7. TYPICAL RUNNING TIME

RSICC machines ran the sample problem within four minutes CPU time.

8. COMPUTER HARDWARE REQUIREMENTS

GMA runs under UNIX operating systems on Sun and IBM RS/6000 workstations and on personal computers.

9. COMPUTER SOFTWARE REQUIREMENTS

At RSICC the code was successfully tested on an IBM RS/6000 model 590 under AIX 4.2 with XLF77 version 3.2.2 and on the Sun Sparc 20 running Sun OS 5.6 (Solaris 2.6) with f77 version 4.2. Executables created with the LAHEY F77L3/EM-32 Version 5.2 compiler are included to run on PCs in a DOS window of Windows95.

10. REFERENCES

a) Included in documentation:

W. P. Poenitz and S. E. Aumeier, "The Simultaneous Evaluation of the Standards and Other Cross Sections of Importance for Technology," ANL/NDM-139, (ENDF-358) (1997).

b) Background information:

W. P. Poenitz, Proc. Conf. On Nuclear Data Evaluation Methods and Procedures, BNL-NCS-51363, Vol. I, 249 (1981).

11. CONTENTS OF CODE PACKAGE

Included in the package are the referenced document in (10.a) and two DS/HD diskettes with a DOS self-extracting compressed file and a compressed Unix tar file which contains installation instructions, Fortran source, PC executables, and a test case.

12. DATE OF ABSTRACT

July 1998.