Program - Brookhaven National Laboratory

LA 5 5:00 PM
Measurements relevant to high energy neutron spectrum (> 10 MeV) by using Yttrium
threshold detectors
M. Bielewicz, S. Kilim, E. Strugalska-Gola, M. Szuta, A. Wojciechowski
National Centre for Nuclear Research, Otwock-Swierk 05-400, Poland
M. Kadykov, S. Tyutyunnikov
Joint Institute for Nuclear Research, 141980 Dubna, Russia
V. Wagner, O.Svoboda
Nuclear Physics Institute of CAS, 25068 Rez, Czech Republic
Study of deep subcritical electronuclear systems and radioactive waste transmutation using relativistic
beams from the accelerator, which we are involved in, is performed within the project “Energy and Transmutation
of Radioactive Wastes” (E&T RAW). This work is a preliminary step toward the study of the
physical properties of ADS systems, in which a deeply subcritical active core is irradiated by a pulsed beam
of relativistic deuterons. The long-range goal is the study of the possibilities of such systems with maximally
hard neutron spectrum, to carry out transmutation of RAW. Results of two different experiments
“Quinta” (2011) and “Energy plus Transmutation” (2006-2009) are presented. The experiment assemblies
(U/Pb model about 1m length) was irradiated by 1 to 6 GeV deuteron beam (Dubna NUCLOTRON) and
we obtain neutron energy spectrum inside whole 3D model by using threshold energy reaction in yttrium
(Y-89) probes. The average neutron flux density per deuteron in three neutron energy ranges (11,5-20.8,
20,8-32.7, 32,7-100 MeV) for the different deuteron beam energies is presented. Main different between
those two experiments is the type of core (target), lead or natural uranium. Theoretical calculations give
us information about quite big different in average neutron flux density in those two cases. We will try to
prove and show it on base of experimental data.
LA 6 5:15 PM
Neutron Capture Reaction on 173 Lu Isotope at DANCE
O. Roig, C. Theroine, A. Ebran, V. Méot
CEA, DAM, DIF, F-91297 Arpajon, FRANCE
E.M. Bond, T.A. Bredeweg, A.J. Couture, R.C. Haight, M. Jandel, F.M. Nortier, J. O’Donnell, R.S.
Rundberg, W. A. Taylor, J.L. Ullmann, and D.J. Vieira
Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
A highly gamma radioactive target, 3.7 GBq, of 173 Lu isotope was placed inside the DANCE array [1]
(Detector for Advanced Neutron Capture Experiments) at Los Alamos to study the neutron radiative
capture on an unstable isotope. This target was produced using successively, proton irradiation of Hf sample
at the Isotope Production Facility, chemical separation of Hf and Lu in hot cell and electrodeposition at Los
Alamos. A 100 µ g/cm 2 relatively pure target of 173 Lu was obtained containing a fraction of 175 Lu used in
the data analysis as a reference. Measurements of radiative capture cross section on 173 Lu were achieved at
the LANSCE spallation neutron source facility in Los Alamos over the neutron energy range from thermal
up to 1 keV. A special configuration was necessary to perform the experiment using the DANCE array due
to the high gamma activity of the target. We will report on the target production, the experiment and
the results obtained for the radiative capture on 173 Lu. Radiative capture cross section will be obtained
for the first time on this unstable nucleus. Some resonances could be characterized. A comparison with a
recent data evaluation will be presented. This work has benefited from the use of the Lujan Center at the
Los Alamos Neutron Science Center, funded by the DOE Office of Basic Energy Sciences and Los Alamos
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