1. European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei München, Germany
2. Helmholtz Institut für Strahlen und Kernphysik, Universität Bonn, Nussallee 14–16, D-53115 Bonn, Germany
3. Astronomical Institute, Charles University in Prague, V Holešovičkách 2, CZ-180 00 Praha 8, Czech Republic
4. Astrophysics Group, Keele University, Keele ST5 5BG, UK
5. Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Correo Central, Santiago, Chile
6. Dipartimento di Fisica e Astronomia Galileo Galilei, Vicolo Osservatorio 3, I-35122 Padova, Italy
7. Research & Scientific Support Department, ESA ESTEC, Keplerlaan 1, NL-2200 AG Noordwijk, the Netherlands
8. European Southern Observatory, Alonso de Córdova 3107, Casilla 19001, Santiago, Chile