Program - Brookhaven National Laboratory

Neutron capture measurements of dysprosium were performed at the electron linear accelerator facility of
the Rensselaer Polytechnic Institute by using the time-of-flight technique in the energy region from 10 eV
to 1 keV. The neutron capture experiments were made with a 16-section NaI multiplicity detector at a
flight path length of 25.5 m. High purity isotopic samples of 161Dy, 162Dy, 163Dy, 164Dy as well as one
natural dysprosium sample with thickness of 0.508 mm were prepared for this measurement. Resonance
parameters were extracted from the data using simultaneous fit with the multilevel R-matrix Bayesian code
SAMMY 8.0. New resonances are proposed, and other resonances previously identified in the literature
have been revised. The resonance Integral (RI) was calculated for each dysprosium isotope using the codes
NJOY and INTER. The resonance integrals calculated for both present and ENDF/B-VII.0 parameters
within the energy region of 0.5 to 20 MeV. The present results are compared with other evaluated values
of ENDF/B-VII.0 and JENDL 4.0.
PR 53
Neutron Yields from the Thick Targets Bombarded with Deuterons Above 20 MeV
Changlin Lan, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
Tao Ye, Institute of Applied Physics and Computational Mathematics, Beijing 100094, China. Yukinobu
Watanabe, Department of Advanced Energy Engineering Science, Kyushu University, Kasuga, Fukuoka
816-8580, Japan. Weili Sun, Institute of Applied Physics and Computational Mathematics, Beijing
100094, China. Kazuyuki Ogata, Research Center of Nuclear Physics (RCNP), Osaka University, Ibaraki
567-0047, Japan.
The reliable thick target neutron yields (TTNYs) data of the deuteron incident nuclear reactions are
important for various applications, especially for the deuteron-energy range of 20-40 MeV, which will be
used in the safety design of the IFMIF. From the literatures, the data on these subjects have been measured
and simulated by some laboratories in the past years. But the data are still scarce such as the outgoing
neutron angles and the kinds of target materials. Meanwhile, there are discrepancies between the measured
and calculated results which used the Monte Carlo code directly. To improve the understanding of the
experimental data, a hybrid method is proposed to estimate the TTNYs bombarded with deuterons above
20 MeV, by including the nuclear models for deuteron breakup reactions. To estimate completely the thick
target yield of deuteron induced reaction, it is necessary to incorporate the theoretical studies between
the nuclear models and the particle transportation methods. At first, a model calculation is employed
to produce the data file, which analyzes the nucleon production from deuteron breakup reaction by the
continuum discretized coupled-channels method and the Glauber model. Next, we simulate the deuteron
and neutron transport processes in the thick samples, and give the output neutron flux.
PR 54
Transmission and Capture Yield Calculations in the Nuclear Data Evaluation Code Conrad
O. Litaize, P. Archier, CEA, DEN, DER, Physics Studies Laboratory, F-13108 Saint-Paul-lez-Durance,
France. B. Becker, P. Schillebeeckx, EC-JRC-IRMM, Retieseweg 111, B-2440 Geel, Belgium.
This paper deals with the verification and validation of the nuclear reaction models developed in the Conrad
code [1] for the modelling of the neutron induced reactions in the Resolved Resonance energy Range (RRR).
First, this work demonstrates the capability of CONRAD code to calculate cross sections compared with
NJOY [2] code (release 99-259). For both Multi-Level-Breit-Wigner and Reich-Moore approximations of
the R-Matrix theory the average discrepancies between the two codes is lower than 0.003% if the precision
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