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The level structure of 16BEr and the de-excitation mechanism in this nucleus have been studied by radiative capture of thermal neutrons in sampies of natural erbium which give a cross-section contribution of 89.8±2.3 % for 167Er. Interference from the 9.q=2.1 %capture contribution of 166Er was welI known from aseparate study with enriched 166Er sampies. Highresolution measurements of they-ray spectrum have been performed using the Karlsruhe Ge(Li) anti-Compton spectrometer below 2 MeV and a Ge(Li) double-escape spectrometer above 5.

Measurements of the 241 Am(n,2n) reaction cross section have been performed at the Joint Research Centre (JRC) Geel in the frame of a collaboration between the European Commission (EC) JRC and French laboratories from CNRS and the Commissariatà L'Energie Atomique (CEA) Cadarache. Raw material coming from the Atalante facility of CEA Marcoule has been transformed by JRC Karlsruhe into suitable 241 AmO 2 samples embedded in Al 2 O 3 matrices specifically designed for these measurements. The irradiations were carried out at the 7-MV Van de Graaff accelerator. The 241 Am(n,2n) reaction cross section was determined relative to the 27 Al(n,α) 24 Na standard cross section. The measurements were performed in four sessions, using quasi-monoenergetic neutrons with energies ranging from 8 to 21 MeV produced via the 2 H(d,n) 3 He and the 3 H(d,n) 4 He reactions. The induced activity was measured by standard γ -ray spectrometry using a high-purity germanium detector. Below 15 MeV, the present results are in agreement with data obtained earlier. Above 15 MeV, these measurements allowed the experimental investigation of the 241 Am(n,2n) reaction cross section for the first time. The present data are in good agreement with predictions obtained with the TALYS code that uses an optical and fission model developed at CEA.

Advanced nuclear fuel cycles are being developed in order to reduce the long-term radiotoxicity of highly radioactive waste. Pyrochemical partitioning techniques appear particularly attractive for advanced fuel cycles in which the minor actinides are recycled. The electrochemical processes of practical importance are the electrorefining process and the liquid-liquid extraction of transuranic (TRU) elements from fission products using either non-miscible molten metal or molten salt-metal phases. Analytical methods for the accurate assay of actinide elements in these matrices needed to be developed. A quantitative assay is required in order to establish a material balance for process development and -at a later stage -for accountancy and control purposes. To this end radiometric techniques such as energy-dispersive X-ray fluorescence analysis (XRF), neutron coincidence counting (NCC) and high-resolution gamma spectrometry (HRGS) were extensively employed for the quantitative determination of actinides (U, Np, Pu, Am, Cm) in process samples. Comparative analyses were performed using inductively coupled plasma mass spectrometry (ICP-MS). The respective samples were available in small quantities ( ∼ = 100 mg) either in the form of eutectic salt or in metallic form with Cd, Zr or Bi as major metallic matrix constituents.

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