Program - Brookhaven National Laboratory

Present Status of Evaluated Nuclear Data Library for Accelerator-Driven Systems in China
Yinlu Hana, Qingbiao Shen, China Institute of Atomic Energy, P.O. Box 275(41), Beijing 102413,
People’s Republic of China. Chonghai Cai, Department of Physics, Nankai University, Tianjin 300071,
People’s Republic of China. Zhengjun Zhang, Department of Physics, Northwest University, Xi’an
710069, People’s Republic of China. Tieshuan Fan, State Key Laboratory of Nuclear Physics and Nuclear
Technology and School of Physics, Peking University, Beijing 100871, People’s Republic of China.
The Aaccelerator-Driven System (ADS) is defined as a system driven by energetic particles of GeV range
accelerated by a so-called high power accelerator incorporated normally with a target of a heavy element,
which generates intense secondary particles, e.g., neutron, proton, etc., via the spallation nuclear
process. The application of the scheme involves the nuclear transmutation for high level nuclear waste
(HLW), plutonium burner for proliferation resistance, the energy production, fissile or tritium fuel breeding,
neutron sources for material irradiation, neutron scattering science, industrial applications, and so
on. To address these needs, a program is under way to develop new evaluated nuclear data libraries
for incident protons and neutrons up to 200 MeV for a range of high-priority elements in the ENDF/B
format. These evaluations are based on a combination of nuclear model calculations and measured
data to evaluate cross sections. The theoretical model code UNF has been made based on the frame
of the optical model, the unified Hauser-Feshbach and exciton model which includes Iwamoto-Harada
model at incident neutron energies below 20 MeV. To keep the energy balance, the recoil effects are
taken into account for all of the reaction processes. The nuclear reaction models code MEND which
can give all kinds of reaction cross sections and energy spectra for six outgoing light particles (neutron,
proton, alpha, deuteron, triton, and helium) and various residual nuclei in the energy range up to 250
MeV, has been developed. Fission is included as a decay channel, that is, a fission competitive width
can be estimated at every step of the cascades. Fifteen uncoupled fission barriers are used to represent
the fission system and describe different channels, respectively. All cross sections of neutron induced
reactions, angular distributions, energy spectra and double differential cross sections are consistent
calculated and evaluated for 23 Na, 24,25,26 Mg, 27 Al, 28,29,30 Si, 40,42,43,44,46,48 Ca, 50,52,53,54 Cr, 54,56,57,58 Fe,
59 Co, 58,60,61,62,64 Ni, 63,65 Cu, 90,91,92,94,96 Zr, 93 Nb, 92,94,95,96,97,98,100 Mo, 180,182,183,184,186 W, 204,206,207,208 Pb,
209 Bi, 232 Th, 237 Np, 232,233,234,235,236,237,238,239,240 U, 236,237,238,239,240,241,242,243,244,246 Pu, 241,242m,242,243 Am
and 243,244,245,246,247,248 Cm at incident neutron and proton energies below 200 MeV, based on the nuclear
theoretical models. All cross sections of proton induced reactions, angular distributions, energy
spectra and double differential cross sections are consistent calculated and evaluated for 27 Al, 28,29,30 Si,
40,42,43,44,46,48 Ca, 50,52,53,54 Cr, 54,56,57,58 Fe, 59 Co, 58,60,61,62,64 Ni, 63,65 Cu, 90,91,92,94,96 Zr, 92,94,95,96,97,98,100 Mo,
180,182,183,184,186 W, 204,206,207,208 Pb, 209 Bi, 232 Th, and 235,238 U at incident neutron and proton energies below
200 MeV. Theoretical calculated results are compared with existing experimental data, and ENDF/B7
and JENDL-3. Good agreement is generally observed between the calculated results and the experimental
data. Since the improved Iwamoto-Harada model has been included in the exciton model for the light
composite particle emissions, the theoretical models provide the good description of the shapes and magnitude
of the energy spectra and double differential cross section of emission deuteron, triton, helium and
alpha. The evaluated data is stored using ENDF/B7 high-energy format.
Corresponding author: Yinlu Han
PR 23
Evaluation of Neutron-Induced Reaction Cross Sections of Ta-181
G. Schnabel, H. Leeb, V. Wildpaner, Atominstitut, TU Wien, Wiedner Hauptstr. 8-10, 1040 Wien,
Austria. D. Neudecker, T-2, Theoretical Division, Nuclear and Particle Physics, Astrophysics &
Cosmology, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
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