1. Commissariat á l’Energie Atomique DEN/DER/SSTH/LMDL, 17 rue des Martyrs, 38054 Grenoble cedex 9, France
2. Japan Atomic Energy Agency Advanced Nuclear System Research and Development Directorate Oarai Research and Development Center, 4002 Narita O-Arai, Ibaraki-Ken 311-1393, Japan