Program - Brookhaven National Laboratory

the global children health and consequently avoid malnutrition. Our method intends to have maximum
reliability and at the same time be as simplest as possible from an experimental point of view. Additionally,
we use this method to determine some contaminants such as Pb, As and Hg that could be present in children
living in neighboring areas to mines and industries. Our work is complemented by some biological and
medical tests.
Corresponding author: G. M Ramirez Avila
PR 31
Characterization of 235 U Targets for the Development of a Secondary Neutron Fluence
Standard
J. Heyse, R. Eykens, A. Moens, A. Plompen, P. Schillebeeckx, G. Sibbens, D. Vanleeuw, R. Wynants, EC
- JRC - IRMM, Retieseweg 111, B - 2440 Geel. M. Anastasiou, National Technical University of Athens,
Department of Physics, Zografou Campus, Athens 157 80, Greece.
The MetroFission project, a Joint Research Project within the European Metrology Research Program
(EMRP), aims at addressing a number of metrological problems involved in the design of proposed Generation
IV nuclear reactors. As part of this project a secondary neutron fluence standard is being developed
and tested at the neutron time-of-flight facility GELINA of the JRC Institute for Reference Materials and
Measurements (IRMM). This secondary standard will help to arrive at the neutron cross section measurement
uncertainties required for the design of new generation power plants and fuel cycles. Such a neutron
fluence device contains targets for which the neutron induced cross section is considered to be a standard.
A careful preparation and characterization of these samples is an essential part of the development of the
secondary standard. In this framework a set of 235 U targets has been produced by vacuum deposition of
UF4 on aluminum backings by IRMM’s target preparation group. These targets have been characterized
for both their total mass and mass distribution over the sample area.
PR 32
Neutron Spectrum Determination of the p(35 MeV)-Be Source Reaction by the Dosimetry
Foils Method
M. Stefanik, Nuclear Physics Institute of The Academy of Sciences of the Czech Republic, pri, Rez 130,
Rez, Czech Republic, 250 68;. P. Bem, M. Gotz, M. Majerle, J. Novak, E. Simeckova, Nuclear Physics
Institute of The Academy of Sciences of the Czech Republic, pri, Rez 130, Rez, Czech Republic, 250 68.
K. Katovsky, Brno University of Technology, Faculty of Electrical Engineering and Communication,
Technicka 10, Brno, Czech Republic, 616 00.
The cyclotron based neutron generators of the broad- and quasi-monoenergetic spectra are operated at
the NPI Rez Fast Neutron Facility utilizing the variable-energy proton beam (up to 37 MeV) and the
D2O (flow), Be (thick), and 7 Li(C) target stations. The intensity and the energy range of the produced
neutron fields are suitable for the integral and differential validation of the neutron cross-sections within
the ADTT- and fusion-relevant (IFMIF) research programs. In the neutron activation experiments, the
irradiated samples are usually fixed in the vicinity of the source target, and the dimensions of the target and
samples are comparable with the target-to-sample distance. Therefore, to determine the neutron spectral
flux at the sample position from the cross-section data, a simple employment of the 1/r 2 law is not relevant.
Instead, the MCNPX calculations are required to take into account the space and energy integration of
neutron yield observables over the geometry arrangement of activation experiment. Due to a usual lack of
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