INTERNATIONAL ATOMIC ENERGY AGENCY NUCLEAR DATA SERVICES DOCUMENTATION SERIES OF THE IAEA NUCLEAR DATA SECTION

IAEA-NDS-174
March 1997

FENDL2/A-MCNP, FENDL2/A-VITJ_E

and FENDL2/A-VITJ_FLAT

The processed FENDL-2 neutron activation cross-section data files

Summary documentation
by
A.B. Pashchenko and H. Wienke

Abstract: This document summarizes the libraries of neutron activation cross-section data processed into the following three formats: continuous energy format as used by the Monte Carlo neutron/photon transport code MCNP4A; VITAMIN-J 175 multigroup format weighted with the VITAMIN-E weighting spectrum as used by the transmutation codes REAC*2/3 and FOUR ACES; VITAMIN-J 175 multigroup ENDF-6 format, with a flat weighting spectrum. The data are available from the IAEA Nuclear Data Section online via INTERNET, or on magnetic tape.

Note:

The IAEA-NDS-reports should not be considered as formal publications. When a nuclear data library is sent out by the IAEA Nuclear Data Section, it will be accompanied by an IAEA-NDS-report which should give the data user all necessary documentation on contents, format and origin of the data library.

IAEA-NDS-reports are updated whenever there is additional information of relevance to the users of the data library.

For citations care should be taken that credit is given to the author of the data library and/or to the data center which issued the data library. The editor of the IAEA-NDS-report is usually not the author of the data library.

Neither the originator of the data libraries nor the IAEA assume any liability for their correctness or for any damages resulting from their use.

96/11

Citation guideline:

This data library should be cited as follows:

A.B. Pashchenko and H. Wienke, "FENDL2/A-MCNP, FENDL2/A-VITJ_E and FENDL2/A-VITJ_FLAT, the processed FENDL-2 neutron activation cross-section data files", report IAEA-NDS-174, International Atomic Energy Agency, March 1997

FENDL2/A-MCNP, FENDL2/A-VITJ_E and FENDL2/A-VITJ_FLAT
The processed FENDL-2 neutron activation cross-section data files

Summary documentation by
A.B. Pashchenko and H. Wienke

As part of the FENDL programme a neutron activation cross-section data library has been established under the acronym FENDL/A-2.0 [Ref. 1]. The evaluations for 13006 activation reactions for 739 target nuclides (including metastable states) were selected from different existing activation data files. The data are in pointwise, continuous energy format, i.e. any resonance parameters contained in the original data files have been converted to cross section data. This data library has been processed further into three modes as described below.

FENDL2/A-MCNP version 1

Data processed by F.M. Mann, Westinghouse Hanford Company, U.S.A., into continuous energy format as used by the Monte Carlo neutron/photon transport code MCNP. The basic cross section data file ACTXS1 in the FENDL2 subdirectory [.ACTIVATION.PROCESSED.MCNP] has a size of about 74 Megabytes. The file XSDIR is the MCNP directory of FENDL/A reactions in ACTXS1.

FENDL2/A-VITJ_E version 1

VITAMIN-J 175 multigroup data (ASCII) weighted with the VITAMIN-E neutron weighting spectrum. The data are available in two formats:

The REAC format for use by the transmutation code REAC*2/3, as generated by F.M. Mann. The basic cross section data file REAC.ACT175 is available in subdirectory [.ACTIVATION.PROCESSED.VITJ_E.REAC] and has a size of 29.6 Megabytes. The subdirectory [.PROG] contains FORTRAN code for converting the groupwise data files into the FISPACT and RACC formats.

The LIBOUT format of the code FOUR ACES (ENEA Bologna) with two additional comment lines (copied from the pointwise EAF file) for each reaction, generated with the module UPDATE of the processing code SYMPAL, by R.A. Forrest, UKAEA Culham, U.K. For reaction numbers the ENDF reaction number MT multiplied by 10 has been adopted with the convention that for the excitation of each metastable state the reaction number is increased by one. The material numbers consist of Z, A and an identifier to indicate ground or metastable target (MAT = Z*10000 + A*10 + LIS). The order of the cross sections on the multigroup data file is in accordance with increasing Z, A, LIS, MT and MF (the identifiers LIS and LFS are used to indicate the (isomeric) states of the target and final nucleus, respectively). The cross section data file FENDLG-2.0_175 is available in subdirectory [.ACTIVATION.PROCESSED.VITJ_E.LIBOUT] and has a size of about 10.6 Megabytes.

FENDL2/A.VITJ_FLAT version 1

VITAMIN-J 175 multigroup data (ASCII) weighted with a constant (flat) weighting spectrum. The data, in ENDF-6 (MF=3) format, have been derived, at IAEA/NDS by H. Wienke, from the FENDL/A-2.0 pointwise data with the IAEA pre-processing codes LINEAR/FIXUP/GROUPIE/DICTION [Ref. 2]. Therefore the original data in EAF format were first converted into "processable" ENDF format with the code ECN-B6I [Ref. 3].

The multigroup data in subdirectory [.ACTIVATION.PROCESSED.VITJ_FLAT] are subdivided into 7 data files given below, with the corresponding sizes and materials included:

The format of the multigroup data is essentially that of the MF=3 file of ENDF-6 format with the following deviations:

a. The material number MAT consists of Z and two last digits of A. To describe metastable targets A has been increased by 50, 70 or 80 (m1, m2 or m3 respectively).

b. The identifiers LIS and LFS are used to indicate the (isomeric) states of the target and final nucleus, respectively. Here the convention has been adopted that LFS = 99 means total production cross section; LFS = I means production of ground state (I = 0), m1 (I = 1) and m2 (I = 2) metastable states respectively. The reaction nomenclature is that of the ENDF format, except that reaction numbers leading to metastable states have been increased by 300 and 600 (for m1 and m2, respectively). In case the isomer production data are included the standard ENDF format notation for the same reaction gives cross sections for production of the ground state (not total "m+g" but simply "g").

Just as in the EAF datafiles the reaction to the ground state is given first, followed by reactions to the metastable states (if any).

References

1. A.B. Pashchenko, H. Wienke, J. Kopecky, J.Ch. Sublet and R. Forrest, "FENDL/A-2.0, Neutron Activation Cross Section Data Library for Fusion Applications", IAEANDS-173, International Atomic Energy Agency, March 1997.
2. D.E. Cullen, "The 1996 ENDF Pre-processing Codes", report IAEA-NDS-39, Rev. 9, International Atomic Energy Agency, November 1996.
3. A.V. Zelenetsky, IATE, Obninsk, Russia (unpublished).

Attachment

DISTRIBUTION OF THE FENDL-2 LIBRARY

(As recommended at the IAEA Advisory Group Meeting on FENDL,

held at IAEA Headquarters, Vienna, Austria, March 1997.)

The master copy of the FENDL-2 library resides with the Nuclear Data Section of the International Atomic Energy Agency. To facilitate user access to the library the official copy of FENDL-2 will be distributed to the major nuclear data centres in Europe (NEA Data Bank, Paris), Japan (JNDC, Tokai-mura), Russia (CJD,Obninsk) and USA (NNDC, Brookhaven and RSIC, Oak Ridge). As agreed between data centers, sharing common FENDL information, the recipients are receiving now the same products from all above centers. The data are available and may be further distributed to the user community according to the customer service options given below. Each FENDL sub-library will be in a single data set, i.e. Activation, Decay, etc. in the 8 mm tape, 6 mm tape, 4 mm tape or standard 9 track magnetic tape (6250 bpi or 1600 bpi) and CD-ROM options. The interested scientists may request FENDL-2 (or parts of it) directly from the IAEA/NDS or from one of these centers.

FENDL CUSTOMER SERVICE OPTIONS

Table notes

1) NNDC will distribute FENDL unprocessed data
2) RSIC will distribute FENDL processed data
3) RSIC offers cost free service to ITER customers