1. Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada
2. Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, Faculté des Sciences de Base, ISIC, Lausanne CH-1015, Switzerland
3. Department of Physics, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom
4. Max-Born Institute, Max-Born-Strasse 2A, D-12489 Berlin, Germany
5. National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
6. Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada