RSICC DATA PACKAGE DLC-274
1. NAME AND TITLE OF DATA LIBRARY
GROUPSTRUCTURES: : VITAMIN-J, XMAS, ECCO-33, ECCO2000 Standard Group Structures..
2. NAME AND TITLE OF DATA RETRIEVAL PROGRAMS
NEA Data Bank, Gif-sur-Yvette, France
and TIB-CALC-DATINV, ENEA-C.R.E Bologna, Italy via the OECD NEA Data Bank, Boulogne-Billancourt, France.
4. HISTORICAL BACKGROUND AND INFORMATION
5. APPLICATION OF THE DATA
Within the International Evaluation Cooperation, four energy group structures for multigroup cross section libraries were defined and adopted. The main purpose is to facilitate the inter-laboratory benchmarking of the evaluated files: ENDF/B-VI, JEF-2, JENDL-3. These group structures are:
1. VITAMIN-J, a 175 neutron and 42 photon group structure aimed at fission and fusion reactor shielding and for fusion blanket shielding (based on VITAMIN-J and -D group structures).
2. XMAS, a 172 neutron group structure, based on group structures formerly used with APOLLO and WIMS. This group structure is aimed at thermal and intermediate spectra cell calculations.
3. ECCO-33, a 33 neutron group structure forming a subset of the VITAMIN-J structure. It is aimed at benchmarking fast reactor criticality calculations.
4. ECCO-2000, a 1968 neutron fine group structure based on a
lethargy grid of 1/120. It contains all the energy boundaries of the group structures VITAMIN-J, XMAS, and ECCO-33.
A computer program is provided for producing a weighting spectrum for group averaging purposes. This spectrum is the one adopted for the VITAMIN-J group cross section libraries and consists of
- temperature dependent thermal Maxwellian
- 1/E slowing down spectrum
- fission spectrum
- fusion spectrum.
The computer produces a table which is linearly interpolable to a specified tolerance.
6. SOURCE AND SCOPE OF DATA
The program replaces the analytical form of the weighting spectrum by a table
of energy versus weight in which the interpolation law is linear-linear. It uses a
multipoint fractional error thinning algorithm to minimize the size of the table.
7. DISCUSSION OF THE DATA RETRIEVAL PROGRAM
8. DATA FORMAT AND COMPUTER
9. TYPICAL RUNNING TIME
E E. Sartori, OECD/NEA Data Bank: Standard Energy Group Structures of
Cross Section Libraries for Reactor Shielding, Reactor Cell and Fusion
Neutronics Applications: VITAMIN-J, ECCO-33, ECCO-2000 and XMAS JEF/DOC-315
Revision 3 - DRAFT (December 11, 1990).
GROUPSTRUCTURES is distributed on one CD
containing documentation, reference material, source files and data. (D00274MNYCP00 NEADB ID: NEA-1344)
12. DATE OF ABSTRACT
KEYWORDS: NEUTRON; PHOTON, SPECTRA