1. NAME AND TITLE

NJOY94.61: Code System for Producing Pointwise and Multigroup Neutron and Photon Cross Sections from ENDF/B Data.

AUXILIARY PROGRAM

UPD 1.3: Portable Update Emulator.

2. CONTRIBUTOR

Los Alamos National Laboratory, Los Alamos, New Mexico.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; Cray, VAX, Sun and IBM RS/6000 workstations (P00355/MFMWS/03).

4. NATURE OF PROBLEM SOLVED

The NJOY nuclear data processing system is a comprehensive computer code system for producing pointwise and multigroup cross sections and related quantities from ENDF/B evaluated nuclear data in the ENDF format, including the latest US library, ENDF/B-VI. The NJOY code works with neutrons, photons, and charged particles and produces libraries for a wide variety of particle transport and reactor analysis codes.

5. METHOD OF SOLUTION

NJOY94.61 consists of a set of modules, each performing a well-defined processing task. Each of these modules is essentially a separate computer program linked together by input and output files and a few common constants. The methods and instructions on how to use them are documented in the LA-12740-M report on NJOY91 and in the "README" file. No published document is planned for NJOY94, which is an interim release on the way to the next version. NJOY94.0 included all the changes in NJOY91.118, the up119 patch, the PostScript plotting package, the new LEAPR module for computing thermal scattering laws, and a major update to PURR incorporating a new version of the unresolved resonance probability table method including temperature correlations.

The November 1995 update to RSIC's package was to replace NJOY94.5, which was packaged in June 1995 with NJOY94.10, which was used to process all of the materials from ENDF/B-VI Release 3 into PENDF format, ACE format, and a 69-group library. In the course of this work, a few additional problems were found and corrected by updates 6-10, which involve changes to the therm, error, acer and njoy modules. Details on the August 1996 NJOY94.35 can be found in the README35 file. In December 1996 the package was upgraded to NJOY94.61. See the README61 file for details.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

All eight test cases ran in less ten minutes on an IBM RS/6000 Model 590.

8. COMPUTER HARDWARE REQUIREMENTS

NJOY94 runs on Cray computers. Machine-specific updates are included for Cray, VAX, Sun, and IBM RS/6000 and DEC Alpha workstations.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran 77 compiler is required. This system runs on Cray under either UNICOS or CTSS, on the VAX under VMS, on the Sun under either Sun OS4 or OS5, IBM RS/6000 under AIX and on DEC Alpha under OSF/1. The CFT77 compiler was used under UNICOS. RSIC tested this release on a SunSparc 5 running SUN OS 5.3 using the Fortran 2.0 compiler and on the IBM RS/6000 Model 590 under AIX 3.2.5 using the XLF 3.2.2.3 compiler. NJOY94 produces graphs directly in Postscript and no longer requires the proprietary DISSPLA software.

10. REFERENCES

R. E. MacFarlane, "README: NJOY 94.61" (December 1996).

R. E. MacFarlane and D. W. Muir, "The NJOY Nuclear Data Processing System Version 91," LA-12740-M (October 1994).

R. E. MacFarlane, "New Thermal Neutron Scattering Files for ENDF/B-VI, Release 2," LA-12639-MS (ENDF 356) (March 1994).

R. E. MacFarlane and D. C. George,"UPD: A Portable Version-Control Program," LA-12057-MS (April 1991).

R. E. MacFarlane, "How to NJOY ENDF-6," The International Workshop on NJOY, Saclay, France (April 1992).

11. CONTENTS OF CODE PACKAGE

Included are the referenced documents and the NJOY94 and UPD source codes, updates, makefiles, selected ENDF/B data sets for test cases, sample problem input and output. The package is available on either CD-ROM, DC 6150 (150 MB), 4 mm DAT (8 GB), or 8 mm (2.3 GB) cartridge tape in tar format.

12. DATE OF ABSTRACT

June 1995, revised November 1995, August 1996, December 1996.

KEYWORDS: COVARIANCE DATA PROCESSING; ENDF/B-V; ENDF FORMAT; GAMMA- RAY CROSS SECTION PROCESSING; GAMMA-RAY PRODUCTION CROSS SECTION PROCESSING; KERMA; MULTIGROUP CROSS SECTION PROCESSING; NEUTRON CROSS SECTION PROCESSING; WORKSTATION