1. NAME AND TITLE OF DATA LIBRARY

BUGLE: Coupled 45 Neutron 16 Gamma-Ray, P3, Cross Sections for Studies by the ANS 6.1.2 Shielding Standards Working Group on Multigroup Cross Sections.

2. NAME AND TITLE OF DATA RETRIEVAL PROGRAMS

LIBGEN: A Computer Program to Generate an Unformatted Cross Section Tape for Output to ANISN.

3. CONTRIBUTOR

Oak Ridge National Laboratory, Oak Ridge, Tennessee.

4. HISTORICAL BACKGROUND AND INFORMATION

Cross section libraries were being used in light-water reactor shielding applications which were not designed for that purpose and were based on early versions of evaluated data files. In 1975 the ANS-6 Radiation Protection and Shielding Subcommittee of the American Nuclear Society Standards Committee formed a working group (ANS-6.1.2) to explore the possibility of defining specifications and selecting reference data which could be recommended for use in lightwater reactor shielding applications.

In mid-1977 a first-round library, intended for ANS-6.1.2 consideration, was prepared by Oak Ridge National Laboratory under the sponsorship of the Electric Power Research Institute and made available for distribution by RSIC.

5. APPLICATION OF THE DATA

The initial application of the library was for radiation transport through concrete. Results were obtained with BUGLE and compared with calculations using DLC-23/CASK, DLC-31/(DPL-1/FEWG1), and DLC-41/VITAMIN C.

6. SOURCE AND SCOPE OF DATA

The present library was collapsed from the DLC-41/VITAMIN-C 171-neutron, 36-gamma-ray-group library. The manipulation operations were accomplished using retrieval modules of the AMPX system. The BONAMI module is used to perform the self-shielding by iteration and interpolation on Bondarenko factors. The nuclides were self-shielded assuming an homogeneous medium of concrete. The self-shielded neutron interaction (171g) AMPX interface was run through CHOX along with photon-production (171-neutron, 36- gamma-ray-groups) and interaction (36g) AMPX interfaces to form a combined (171,36) interface. The NITAWL module was used to convert the resulting combined AMPX interface into an AMPX working library format which was then fed into XSDRNPM to perform the collapse to 45-neutron and 16-gamma-ray groups with weighting as described below.

The weighting function to generate the 171-group library is as follows:

FUNCTION ENERGY RANGE

Maxwellian (300 K) 105eV to 0.125 eV

1/E 0.125 eV to 820.8 keV

fission spectrum 820.8 keV to 10.0 MeV

1/E 10.0 MeV to 12.57 MeV

fusion peak 12.57 to 15.57 MeV

1/E 15.57 to 17.333 MeV

A 171-group version of the original weighting function was used to perform the collapse to 45 neutron broad groups. Flat weighting was used to generate the original 36-gamma-ray-group data and to perform the collapse.

The nuclides are:

1H, 2H, 3H, 3He, 4He, 6Li, 7Li, 9Be, 10B, 11B, 12C, 14N, 16O, F, 23Na, Mg, 27Al, Si, 31P, 32S, Cl, K, Ca, Ti, V, Cr, 55Mn, Fe, 59Co, Ni, Cu, Zr, Zircalloy 2, 93Nb, Mo, 107Ag, 109Ag, Cd, Sn, Ba, 151Eu, 153Eu, 181Ta, 182W, 183W, 184W, 186W, Pb, 232Th, 233U, 234U, 235U, 236U, 237Np, 238U, 239Pu, 240Pu, 241Pu, 242Pu, 241Am.

There are 66 "materials" in the library. Data are given for 61 materials self-shielded for concrete, 1 for iron, and 4 for stainless steel.

Several of the materials were not available from the ENDF/B-IV data file. Data for 31P, 32S, natural Zr, Sn, and Ba were obtained from the Lawrence Livermore (LENDL) data library. Data for the tungsten isotopes were obtained from the DNA library.

7. DISCUSSION OF THE DATA RETRIEVAL PROGRAM

LIBGEN is a modified version of the Library Generation Routine which is available in the CCC-254/ANISN code package. This version will read data from a card image tape, the mode by which BUGLE is distributed and write an unformatted tape for direct use with ANISN.

8. DATA FORMAT AND COMPUTER

Fortran IV and BCD card images; IBM 360.

9. TYPICAL RUNNING TIME

To read the data, form a card image tape, and rewrite it on an unformatted tape requires 2 minutes on the IBM 360/91 computer.

10. REFERENCES

a. Included in the documentation:

R. W. Roussin and C. R. Weisbin, "Few-Group Library for Use by ANS-6.1.2," Informal Notes (1977).

J. T. West, G. P. de Beer, B. Nakhai, R. W. Roussin, "Developing an ANS Coupled Cross Section Standard for Concrete Shielding," Informal Notes (1977).

b. Background information:

R. W. Roussin, C. R. Weisbin, J. E. White, N. M. Greene, R. Q. Wright, J. B. Wright, The CTR Processed Multigroup Cross Section Library for Neutronics Studies, ORNL/RSIC-37 (To be published).

11. CONTENTS OF LIBRARY

Included are the referenced documents (10.a) and one tape cartridge in tar format which contains the 61 group coupled cross sections in BCD card images, the source program written in Fortran IV, sample problem data in BCD card images, and the sample problem output-list.

12. DATE OF ABSTRACT

September 1977; update December 1980.