1. Department of Physics and Astronomy, Leicester Institute of Space and Earth Observation, University of Leicester, University Road, Leicester LE1 7RH, UK
2. Astrophysics Research Centre, School of Mathematics and Physics, Queen’s University Belfast, BT7 1NN Belfast, UK
3. Astrophysics Group, Cavendish Laboratory, J.J. Thomson Avenue, Cambridge CB3 0HE, UK
4. Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
5. Observatoire de Genève, Université de Genève, 51 Ch. des Maillettes, 1290 Sauverny, Switzerland
6. Institute of Planetary Research, German Aerospace Center, Rutherfordstrasse 2, 12489 Berlin, Germany
7. Departamento de Astronomía, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Chile
8. Instituto de Astronomía, Universidad Católica del Norte, Av. Angamos 0610, Antofagasta, Chile