1. NAME AND TITLE

REAC*3: Computer Code System for Activation and Transmutation.

2. CONTRIBUTOR

Hanford Engineering Development Laboratory, Richland, Washington.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; CRAY, IBM RS/6000, SUN, DEC, SGI (C00443/MFMWS/00).

PC486 (C00443/IBMPC/00).

4. NATURE OF PROBLEM SOLVED

REAC is a computer code system for fast calculation of activation and transmutation. It is used to predict transmutations in various magnetic fusion energy (MFE) test facilities and conceptual reactors. The REAC system has been used to calculate activation in FMIT and, also, to calculate solid and gaseous transmutations in various neutron environments. In April 1996, RSIC packaged REAC*3 which is very similar to REAC*2. In addition to being much more easily ported to different computer systems, the main changes to REAC*3 are:

1) the fixing of a few minor bugs (the most severe being that the time unit "d" was outputted as "h"),

2) the inclusion of the option to use inputted reaction rates in addition to those calculated from flux and cross sections,

3) the inclusion of zones,

4) the production of input to plotting programs

5) the inclusion of filenames (including paths) up to 64 characters in length.

5. METHOD OF SOLUTION

The system consists of a driver code, cross-section libraries, flux libraries, a material, and a decay library. REAC first finds the flux for the desired facility (in the case of neutrons) or the slowing down relation (in the case of charged particles). The isotopic composition of the desired material is then determined. The desired cross-section library is searched for these isotopes, and the multigroup cross sections are folded with the multigroup flux to obtain reaction rates.

After the transmutations are calculated, REAC sorts the isotopes into elements as a transmutation file, determines the decay rate of the radioactive isotopes, finds the gamma spectra from each nucleus, and sorts the products in terms of decay rates. When the program is run for a series of time periods, the material composition is obtained for each time period from the result of the previous time period. Thus the number of isotopes included in the calculation can increase.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

On IBM RISC 6000/Model 590 AIX 3.2.5:

1) binlib Time in seconds

runs

cross.30v 7.9

cross.30b 8

cross.63 0.1

cross 99 25.9

cross 175 42.2

decay.193 2.4

mat 0.2

flux 0.2

element 0.1

isotope 0.1

2) reac3 1.2

3) lstcon 0.3

8. COMPUTER HARDWARE REQUIREMENTS

REAC*3 was developed on a Cray under UNICOS and has been tested on Unix workstations and on PC. At least 20MB memory and 120 MB disk space are required.

9. COMPUTER SOFTWARE REQUIREMENTS

REAC*3 was tested at RSIC on these Unix systems:

IBM RISC 6000 under AIX 3.2.5, XL FORTRAN 3.2.2.3

SUN Sparc 20 under Solaris 2.4, Sun FORTRAN 77 Version 2.0

Silicon Graphics Indy under IRIX 5.3, FORTRAN 77 Version 4.0.2

DEC Alpha under DEC/UNIX 3.2C, DEC FORTRAN 3.8

The code was also tested at RSIC with the Lahey FORTRAN 90 Version 1.10h compiler on the PC-486/DX2 (66MHz) with 32 megabytes of memory under the MS-DOS system of Windows 95 operating system.

10. REFERENCES

F. M. Mann, "reac3.doc" (December 28, 1990).

B. L. Kirk, READMEs (installation instructions) (April 1996).

F. M. Mann, "REAC*2: Users Manual and Code Description," WHC-EP-2082 (December 1989).

F. M. Mann, "REAC*3 Nuclear Data Libraries," Proceedings for International Conference on Nuclear Data for Science and Technology, Julich, Germany (May 1991).

11. CONTENTS OF CODE PACKAGE

The package includes referenced documents and Fortran source, scripts, data, test case input and output, plus an executable for the PC version. The Unix version is transmitted on either one CD-ROM, DC 6150 (150 MB), 4-mm DAT (8 GB), or 8-mm (2.3 GB) cartridge tape in compressed a tar file. The PC version is transmitted on one CD-ROM written in DOS format.

12. DATE OF ABSTRACT

October 1983, revised April 1996.