1. Aix-Marseille Université, CNRS, PIIM UMR 7345, FR-13397 Marseille Cedex 20, France
2. Department of Fusion Plasma Physics, Royal Institute of Technology (KTH), Teknikringen 31, 100 44 Stockholm, Sweden
3. CAMECA SAS - 29 Quai des Grésillons, 92622 Gennevilliers Cedex, France