Program - Brookhaven National Laboratory

PR 104
Evaluations for n+ 54,56,57,58,nat Fe Reactions Below 20MeV
Jing Qian, Tinjin Liu, Zhigang Ge, China Nuclear Data Center, China Institute of Atomic Energy.
Based on the evaluated experimental data of total, nonelastic scattering cross sections and elastic scattering
angular distributions, a set of neutron optical model potential parameters were obtained by APMN code.
All cross sections of neutron induced reactions, angular distributions, energy spectra, double differential
cross sections and γ production data were consistently calculated and analyzed for 54,56,57,58,nat Fe at incident
neutron energies below 20 MeV with theory codes DWUCK and UNF which are based on the nuclear
theoretical models. Evaluated results were compared with available experimental data and evaluated data
from ENDF/B-VII.0 and JENDL-3.3. Especially, consistence adjusting was done between natural elememt
and its isotopes in order to make the cross section of natural Fe equal to the weight sum of its isotopes.
Furthermore, experimental data of 54 Fe(n, 2n) cross sections below 20MeV were analyzed and evaluated
with corrections and normalization. The data were processed in terms of a fitting by a spline code with
the consideration of correlation errors. The corresponding covariance matrixes of experimental data were
constructed with the information on experimental errors and correlation errors.
PR 105
Evaluated Activation Cross Section Data for Proton Induced Nuclear Reactions on W up
to 3 Gev Incidence Energy
A.Yu. Konobeyev, U. Fischer, P.E. Pereslavtsev, Institute for Neutron Physics and Reactor Technology,
Karlsruhe Institute of Technology, Postfach 3640, 76021 Karlsruhe, Germany. D. Ene, European
Spallation Source ESS AB, P.O.Box 176, SE-221 00 Lund, Sweden.
The target of the European Spallation Source ESS will consist of solid tungsten that will be bombarded by
2.5 GeV protons. During operation numerous hazardous radio-nuclides will be produced in the tungsten
target. These can be assessed by means of inventory calculations provided reliable production data are
available. To this end, a full set of data files has been prepared containing yields of radionuclides produced
in proton induced reactions on tungsten with energies up to 3 GeV. The data were obtained from the
analysis of nuclear model calculations, available experimental data and systematics. The calculations of
cross-sections were performed using the intranuclear cascade model combined with the Hauser-Feshbach
model. The CASCADE code [1] and the TALYS code [2] were applied for numerical calculations. At
relative low projectile energies the pre-equilibrium exciton model and the Hauser-Feshbach model implemented
in TALYS were used for the cross-section calculations. The transition between CASCADE-TALYS
and TALYS calculations was achieved by employing a ”hybrid” approach similar to the one discussed in
Ref.[3]. The available experimental information, results of calculations and systematics were applied for
the evaluation of yields of residual nuclei using statistical methods implemented in computer code package
BEKED elaborated in KIT. Evaluated data were obtained for tungsten isotopes with the mass number
180, 182, 183, 184, and 186.
[1] V.S. Barashenkov, Comp. Phys. Comm. 126 (2000) 28. [2] A.J. Koning, S. Hilairey, M. Duijvestijn,
http:// www.talys.eu/ [3] R.E.Prael, http://www.oecd-nea.org/science/iend.hide/iend 13.pdf
PR 106
316