No abstract available

[en] In order to optimize the neutron shieldings in the NEMO 3 detector we plan to use the MICAP/GEANT code. To study the reliability of this code different experiments have been performed in Bordeaux and Prague using Ge detectors. The germanium detector was placed inside of different types of shieldings (iron, lead, polyethylene) to record the γ-rays emitted in the interactions of the neutrons provided by a ²⁵²Cf source. The high energy resolution of the Ge diode allows identifying the photons coming from inelastic scattering (n,n'γ) and capture reactions (n,γ). In order to understand the neutron behaviour the neutron simulation code MICAP/GEANT which permits the study of the neutron interactions from 10^-5 eV up to 20 MeV was used. By comparing the simulations with the experimental data the processes of thermalization and capture in light (polyethylene) and heavy (iron and lead) materials was tested. Following these tests a new library taking into account the decay schemes of the states excited by the (n,γ) or (n,n'γ) has been developed as well as an interface between this library and the MICAP library. The first results obtained show a good agreement between experiment and simulation

[en] ARRONAX, acronym for ''Accelerator for Research in Radiochemistry and Oncology at Nantes Atlantique'', is a high energy and high intensity cyclotron. It will turn into operation in September 2009 in Nantes (France). It is mainly devoted to the production of radionuclides for medicine. A priority list based on the capability of the machine as well as on the need expressed by the European medical community through a questionnaire has been set. It contains isotopes for imaging (⁸²Sr/⁸²Rb and ₆₈Ge/⁶⁸Ga generators and ⁶⁴Cu, ⁴⁴Sc, ⁵⁵Co) and for therapeutic use (⁶⁷Cu, ⁴⁷Sc and ²¹¹At). In this list, a special attention has been paid to dosimetry, both by giving lower scores of interest to radionuclides with undesirable emissions, such as high energy gammas, and by promoting β+/β- couples of radionuclides (⁶⁴Cu/⁶⁷Cu and ⁴⁴Sc et ⁴⁷Sc). Indeed, pre-therapeutic dosimetry is essential in the development of new radiolabeled therapeutics and PET imaging should prove more precise and accurate in calculating radiation doses received by critical organs and tumors. Arronax and its partners will also devote a large effort to develop targeted alpha-radionuclide therapy. In particular, a radioimmunotherapy project using ²¹¹At coupled to a specific monoclonal antibody will start this autumn to treat prostate cancer patients with high risk of relapse. ARRONAX is an important part of the project since it will have to produce astatine in large amounts on a regular basis. (author)

[en] Experimental light-particle production double-differential cross sections are reported for 62.9 MeV proton-induced reactions on ²⁰⁸Pb. Light charged particle (p, d, t, ³He and ⁴He) double-differential cross sections were measured from 25 to 155 by step of 10 degrees with a set of Si-Si-CsI telescopes. Neutron double-differential cross sections were measured at 24 , 35 , 55 , 80 and 120 with DeMoN counters. Energy-differential, angular-differential and total production cross sections are also presented. These data are compared to theoretical calculations (MCNPX, FLUKA and TALYS). (orig.)

[en] Neutrons and light charged particles produced in 62.9 MeV proton-induced reactions on ²⁰⁸Pb were measured during a single experiment performed at the CYCLONE facility in Louvain-la-Neuve (Belgium). Two independent experimental set-ups were used to extract double differential cross-sections for neutrons, protons, deuterons, tritons, ³He and alpha-particles. Charged particles were detected using a set of Si- Si- CsI telescopes from 25 to 155 , by step of 10 degrees. Neutrons were measured using shielded DeMoN counters, liquid NE213 scintillators, at 24 , 35 , 55 , 80 and 120 . These data allowed the determination of angle differential, energy differential and total production cross-sections. A comparison with theoretical calculations (MCNPX, FLUKA and TALYS) has been performed. It shows that the neutron and proton production rates are well predicted by MCNPX, using the INCL4 option. All the other codes underestimate the neutron production whereas they overestimate the proton one. For composite particles, which represent 17% of the charged particle total reaction cross-section, neither the shape nor the amplitude of the cross-sections are correctly predicted by the models. (orig.)