1. NAME AND TITLE

NJOY97.0: Code System for Producing Pointwise and Multigroup Neutron and Photon Cross Sections from ENDF/B Data.

AUXILIARY PROGRAM

UPD 2.0: Portable Update Emulator.

2. CONTRIBUTOR

Los Alamos National Laboratory, Los Alamos, New Mexico.

3. CODING LANGUAGE AND COMPUTER

Fortran 90 or Fortran 77; Cray, Sun, IBM RS/6000, PC/Linux, PC/DOS (P00368/MNYCP/00).

4. NATURE OF PROBLEM SOLVED

The NJOY nuclear data processing system is a modular computer code used for converting evaluated nuclear data in the ENDF format into libraries useful for applications calculations. Because the Evaluated Nuclear Data File (ENDF) format is used all around the world (e.g., ENDF/B-VI in the US, JEF-2.2 in Europe, JENDL-3.2 in Japan, BROND-2.2 in Russia), NJOY gives its users access to a wide variety of the most up-to-date nuclear data. NJOY provides comprehensive capabilities for processing evaluated data, and it can serve applications ranging from continuous-energy Monte Carlo (MCNP), through deterministic transport codes (DANT, ANISN, DORT), to reactor lattice codes (WIMS, EPRI). NJOY handles a wide variety of nuclear effects, including resonances, Doppler broadening, heating (KERMA), radiation damage, thermal scattering (even cold moderators), gas production, neutrons and charged particles, photoatomic interactions, self shielding, probability tables, photon production, and high-energy interactions (to 150 MeV). Output can include printed listings, special library files for applications, and Postscript graphics (plus color). More information on NJOY is available from the developer's home page at http://t2.lanl.gov. Follow the Tourbus section of the Tour area to find notes from the ICTP lectures held at Trieste in March 1998 on the ENDF format and on the NJOY code.

5. METHOD OF SOLUTION

NJOY97 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 new published document is yet available. NJOY97 is a cleaned up version of NJOY 94.105 that features compatibility with a wider variety of compilers and machines, explicit double precisioning for 32-bit systems, a larger test-problem suite, a new revision control system, and some changes to the user input.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

All 12 test cases ran in about ten minutes on an IBM RS/6000 Model 590.

8. COMPUTER HARDWARE REQUIREMENTS

NJOY97 runs on many computers. Machine-specific updates are included for Cray, Sun, IBM RS/6000, and DEC Alpha workstations, plus Linux and DOS updates for PC. This version has been tested on a Cray YMP with both static and stack-based memory allocation with a Fortran-90 compiler, on a Sun Ultra in 32-bit mode using f90, on a Sun Ultra in 64-bit mode (-dbl) using f77, on a Pentium 90 using linux g77 (32 bits with stack-based memory allocation), on an IBM RS/6000 using f77 (with f90 libraries available), and on NT and Win95 using the DOS-based Lahey LF90 compiler.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran compiler is required is required on Unix systems. NJOY97 produces graphs directly in Postscript and no longer requires the proprietary DISSPLA software. The Unix distribution runs on Cray under UNICOS, on Sun under Solaris, on IBM RS/6000 under AIX, on DEC Alpha under OSF/1, and on PC under Linux. RSICC tested this release on a SunSparc 20 running SUN OS 5.5 using the Fortran 4.2 compiler, on the IBM RS/6000 Model 590 under AIX 4.2 using the XLF 3.2.5 compiler, and in a DOS window of Windows95 on a Pentium using the Lahey Fortran 90 Version 4.0 compiler. Lahey Fortran 90 was used to create the PC executable which is included in the package. NJOY also runs on Intel PC under RedHat Linux 5.0 with the EGCS package replacing the standard gcc compiler package. Redhat users may get the egcs-1.0.2-1.i386.rpm package from ftp://ftp.redhat.com in the /pub/contrib/hurricane/i386 directory. Note that this is not an "official" RedHat package.

10. REFERENCES

R. E. MacFarlane, "README0" (October 31, 1997).

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 NJOY97 and UPD source codes, PC executables, updates, makefiles, selected ENDF/B data sets for test cases, sample problem input and output. The package is transmitted on CD-ROM in both tar and DOS formats.

12. DATE OF ABSTRACT

April 1998.