1. NAME AND TITLE OF DATA LIBRARY
COVFILS-2: Neutron Data and Covariances for Sensitivity and Uncertainty Analysis.
2. NAME AND TITLE OF DATA RETRIEVAL PROGRAMS
BOXR: Reconstruct Complete Matrix from Compressed Format.
Los Alamos National Laboratory, Los Alamos, New Mexico.
4. HISTORICAL BACKGROUND AND INFORMATION
Like the earlier DLC-091/COVFILS 30-group library, COVFILS-2 was produced using modules
of the PSR-171/NJOY nuclear data processing system. The new library includes several additional
5. APPLICATION OF THE DATA
COVFILS-2 is a library of multigroup neutron cross sections, scattering matrices and covariances.
This 74-group library is primarily intended for use in the sensitivity and uncertainty analysis of fusion
integral experiments and fusion reactor systems.
6. SOURCE AND SCOPE OF DATA
COVFILS-2 is largely based on data evaluations from the ENDF/B-V library, although some minor
corrections and improvements were incorporated. In cases where the covariance evaluation is missing
(as in the case of Be) or judged to be inadequate, private Los Alamos evaluations, such as LA-7932-MS, are employed. The COVFILS-2 group structure was chosen to give good energy resolution at
high energies. It is a subset of the Los Alamos 187-group structure used in MATXS8. The groups
are ordered in ENDF/B order (low-to-high) for all vector data and for the covariance matrices. Full
(P0-P3) transfer matrices in normal high-to-low order for all scattering reactions present in the library
are also included. The elements included are:
H, 6Li, 7Li, Be, C, N, O, Na, Al, Si, Cr, Fe, Ni, Pb.
7. DISCUSSION OF THE DATA RETRIEVAL PROGRAM
Both to save space and to simplify the application of these data to uncertainty analyses, redundant
reactions are omitted from COVFILS-2. BOXR reads from Fortran unit 20 those portions of the
library which have been selected by the user and writes the complete matrix to Fortran unit 21. The
input to reconstruct the entire library, which occupies 970,000 lines, is included in file 4 of the
8. DATA FORMAT AND COMPUTER
Card images; Cray, CDC, IBM.
9. TYPICAL RUNNING TIME
The sample problem for only one material took 14 seconds on the IBM 3033 under the MVS
D. W. Muir, "COVFILS-2: Neutron Data and Covariances for Sensitivity and Uncertainty Analysis," Fusion Technology 10(3), Part 2B, pp. 1461-1465 (November 1986).
D. W. Muir, "The Evaluation and Application of Redundant- Cross-Section Covariances," LA-UR-86-3786-Rev (November 1986).
J. W. Davidson, D. J. Dudziak, D. W. Muir, J. Stepanek and C. E. Higgs, "Recent Joint
Developments in Cross-Section Uncertainty Analysis at Los Alamos and EIR," LA-UR-87-219
11. CONTENTS OF LIBRARY
Included are the referenced document and one (1.2MB) DOS diskette which contains the data,
Fortran retrieval source, sample input and output.
12. DATE OF ABSTRACT
KEYWORD: COVARIANCE MATRICES; NEUTRON CROSS SECTIONS; MULTIGROUP CROSS SECTIONS BASED ON ENDF/B