High priority nuclear data request list. The data for long-lived fission products, minor actinides and the thorium cycle

This workshop is organised by the Research Group GEDEON together with CERN, OECD-NEA and the CFDN (French Committee for Nuclear Data). It is the continuation of the one at CERN on September 21 and 22, 1998, jointly organised with EC, GEDEON and OCDE-NEA. This last one is centred on the CERN proposal of a facility for neutron production up to 250 MeV, devoted to neutron data measurements. The first aim of the Paris workshop is to identify the present status of specific nuclear data relevant to innovative options (accelerator driven system - ADS and thorium) in the nuclear fuel cycle, beyond what has been gathered for standard reactors (PWR, FBR) and for the associated fuel cycles based on uranium and plutonium. The following topics were presented and discussed: 1. extension of present evaluated nuclear data files beyond 20 MeV needed to correctly describe the high energy part (up to approximately 200 MeV) of the spallation process used to generate the external neutrons needed for the sub-critical assemblies; 2. differential and integral cross section data in relation with the use of a thorium based; 3. the same for minor actinides and some long-lived fission residues likely to be destroyed in reactors; 4. the same for new type of materials such as lead or lead-bismuth, to be used as spallation target or as cooling, in relation with corrosion and irradiation effects. Beyond these specific issues, ADS will also take advantage of better known nuclear data coming from the existing reactors in operation. Very recent results related to spallation target physics such as neutron and residues production from heavy targets were also presented at this workshop. One very important aim of this workshop is also to bring physicists from different origin, especially from CERN, to cooperate in a program on nuclear data in relation with innovative options. This document brings together two articles entitled ''high priority nuclear data request list. The data for long lived fission products, minor actinides and the thorium cycle'' (J.L. Rowlands, OECD-NEA) and ''the OECD Nuclear Energy Agency's working groups on nuclear data'' (C. Nordborg, OECD-NEA), and all the available transparencies of this workshop: ''radiation-induced damage to structural materials and related needs for structural data in ADTT design''; ''a CERN-PS experimental campaign to measure neutron cross sections from 1 eV to 250 MeV with high resolution''; ''program for neutron data measurements in the fast neutron region (0.1 to 3 MeV)'' (CEN-Bordeaux Gradignan); ''integral experiments: the physics approach'' (CEA-DRN),; ''Mini-Inca, integral measurement relevant for nuclear waste transmutation systems'' (CEA-Saclay/DSM/DAPNIA/SPhN and Inst. Laue Langevin, Grenoble); ''experimental check of neutron cross-sections using slowing down spectrometer (SDS) and accurate Monte-Carlo simulation calculation'' (IN2P3-ISN Grenoble and TARC collaboration); ''recent experimental results on spallation target related data'' (GSI); ''measurements of (n,px), (n,dx), (n,tx) and (n,αx) reactions between 25 and 70 MeV at Louvain-la-Neuve (IPN Louvain-la-Neuve); ''the Subatech and LPCC-Caen proposals''; and ''the proton elastic measurements at AGOR in the range 120-200 MeV (IPN-Orsay)''. (J.S.)