1. Department of Physics, Sophia University, Chiyoda-ku, Tokyo 102-8554, Japan
2. Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
3. Department of Physics, Chungnam National University, Daejeon 305-764, South Korea
4. Research and Marketing Management Dept., New Products Development Div., Kanto Denka, Kogyo Co., Ltd., Chiyoda-ku, Tokyo 101-0063, Japan
5. Shibukawa Development Research Lab., New Products Development Div., Kanto Denka Kogyo Co., Ltd., Shibukawa City, Gunma 377-8513, Japan
6. Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Avenida Complutense, 28040 Madrid, Spain
7. Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (CSIC), Serrano 113-bis, 28006 Madrid, Spain
8. Department of Chemistry, Science Institute, University of Iceland, 107 Reykjavik, Iceland