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Reactors designed by Argonne National Laboratory


ETOE-2 (Fast Reactor Cross Section Processing Codes)


Standard Code Description

  1. Name and Title of Program:
    ETOE-2: A program for ENDF/B to MC22 data conversion.
  2. Computer for Which Program is Designed and Other Machine Version Packages Available:
    IBM 303x, IBM 370, RS6000, SUN
  3. Description of Problem or Function:
    ETOE-2 (ENDF/B to MC22 data conversion) accepts cross-section data from an ENDF/B version 5 or version 6 library tape in binary alternate form and prepares the binary cross section and Legendre polynomial data files for the MC22 processing code. The MC22 data library generated consists of eight files containing (1) the administrative file; (2) function table file; (3) unresolved resonance data; (4) resolved resonance data; (5) smooth tabulated non-resonant data; (6) inelastic and (n, 2n) distributions; (7) fission spectra data; and (8) Legendre data.
  4. Method of Solution:
    The ETOE-2 code accepts the ENDF/B version 5 and 6 formats which permit a large number of options in describing the fundamental data. Many of these options have not been used in the past versions of ENDF/B data, and only a subset of the allowed ENDF/B specifications can be processed by MC22/SDX directly without modifications. The code provides the means to convert various ENDF/B data into the form or energy structure readily amenable to MC22/SDX. For example, the MC22/SDX resolved resonance algorithms assume either a single or multilevel Breit-Wigner or a multilevel Adler-Adler format. The ENDF/B-6 format also permits R-Matrix (Reich-Moore) parameters which ETOE-2 converts to multipole parameters (Ref. 1) that preserve the general features required by the traditional resonance integral concept and the Doppler-broadening algorithm in MC22/SDX without comprimising rigor. Similarly, ENDF/B permits six secondary energy distribution laws for inelastic and (n, 2n) scattering, whereas MC22 permits only three. The ETOE-2 code generates tabular data if the ENDF/B data employ any of the three laws not processed by MC22. Similar examples may be cited in the processing of elastic scattering distributions and fission spectrum data. In general, the format conversions performed by ETOE-2 do not alter the basic data provided on the ENDF/B files.
    The ETOE-2 program thus provides an automated capability for the generation of MC22/SDX library files from ENDF/B data. Currently the ultra-fine-group (ufg) energy structure chosen to form our MC22/SDX libraries is 2082 groups with constant lethergy (1/120) from 15 MeV to .4 eV. Since ETOE-2 is variably dimensioned, any number of ufg lethargy intervals is possible. ETOE-2 generates ufg data for all the ENDF/B representations except resolved and unresolved data and fission spectra data. Since the library files generated by ETOE-2 are not composition dependent, the program need be executed only when new fundamental data become available (e.g., each release of ENDF/B). A limited capability is available to modify the data in the MC22/SDX libraries, thus obviating the need to rerun ETOE-2 in order to study the sensitivity of multigroup cross sections to changes in fundamental data.
  5. Restrictions on the Complexity of the Problems:
    The restrictions on processing capabilities are basically those imposed by the ENDF/B formats and the MC22 program.
  6. Typical Running Time:
    The average running time varies by material processed. It depends on resonance scattering calculations and Legendre polynomial calculations. Roughly one minute of CPU time is required for each material on a SUN SS20 workstation.
  7. Unusual Features of the Program:
    At user option, the ETOE-2 code calculates resonance cross sections from ENDF/B resonance parameters for all materials of mass less than an input value. Generally, a mass of 100 is used. These "light" element resonance cross sections are then combined with the ENDF/B "floor" cross sections and integrated over ultra-fine-group energy boundaries (u = 1/120) to provide the group cross sections required by MC22/SDX. It is assumed that "light" element resonance cross sections are composition-independent on the ultra-fine-group level.
  8. Related and Auxiliary Programs:
    ETOE-2 prepares MC22 binary libraries using a binary alternate form ENDF/B library tape. RIGEL (NESC Abstract 915) can be used to create the ENDF/B binary alternate tape. MERMC22 merges, deletes, or renames materials from one or two input MC22 binary libraries and forms an output MC22 binary library.
  9. Status:
    The MC22 library generated by ETOE-2 containing all of the ENDF/B-V data is available from the Radiation Safety Information Computational Center (RSICC). The MC22 library generated by ETOE-2 containing 45 isotopes of ENDF/B-VI data is available at Argonne. Additional processing of ENDF/B-VI data is continuing.
  10. References:
    1. R. N. Hwang, "A Rigorous Pole Representation of Multilevel Cross Sections and Its Practical Applications," Nuclear Science and Engineering, 96, pp. 192-209 (April 1987).
    2. C. G. Stenberg and R. N. Hill, "Addition of the MC22 Libraries and Updates to the MC22 Code on the RA Workstations (#5)," Argonne National Laboratory Internal Memorandum, August 10, 1993.
    3. ETOE-2, NESC No. 350 ETOE-2 Documentation, National Energy Software Center Note 83-84, August 25, 1983.
    4. H. Henryson, II, B. J. Toppel, and C. G. Stenberg, "MC22: A Code to Calculate Fast Neutron Spectra and Multigroup Cross Sections," Argonne-8144, June 1976.
    5. R. Kinsey, "Data Formats and Procedures for the Evaluated Nuclear Data File, ENDF,
    6. BNL-NCS-50496 (ENDF-102), second edition (ENDF/B-V), October 1979.
    7. Odelli Ozer, Ed., "Description of the ENDF/B Processing Codes and Retrieval Subroutines,
    8. BNL 50300 (ENDF-110), September 1967, revised June 1971.
    9. D. M. Green and T. A. Pitterle, ETOE, "A Program for ENDF/B to MC**2 Data Conversion, APDA-219 (ENDF-120), June 1968.
  11. Machine Requirements:
    On IBM, SUN, and RS6000 computers at least 2000 K bytes of memory are required.
  12. Programming Languages Used:
    FORTRAN-77 is used. The program can be executed entirely in FORTRAN. Optional dynamic memory allocation and timing routines supplied from host machine libraries or code in "C" may be used on UNIX workstations.
  13. Operating System:
    No special requirements are made on the operating system. SunOS 4.1.3x and SOLARIS 2.5 (for SPARCStations), AIX 3.2 on the IBM RS6000, the XMP UNICOS operating system segmentation loader (segldr) and the IBM (MVS/JES3) linkage editor overlay facilities may be used.
  14. Other Programming or Operating Information or Restrictions:
    The standalone source code contains approximately 25,000 FORTRAN statements and 444 C statements.
  15. Name and Establishment of Author or Contributor:
    • C. G. Stenberg
      Nuclear Engineering Division
      Argonne National Laboratory
      9700 South Cass Avenue
      Argonne, Illinois 60439
  16. Materials Available:
    Distribution of this material may be restricted. Electronic UNIX file includes:
    • Export Memo
    • Source Code (FORTRAN and "C")
    • Binary and ASCII data to create a MC22 library from ENDF/B-V data
    • Script and FORTRAN-77 code to convert ASCII data to binary MC22 library
  17. Sponsor:
    U.S. Department of Energy, Office of Nuclear Energy, Science, and Technology.

Last Modified: Wed, April 20, 2016 9:52 AM



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