1. Department of Astronomy and Astrophysics, The University of Manchester, Manchester M13 9PL, UK
2. Department of Physics & Laboratory for Space Research, The University of Hong Kong, Hong Kong SAR, China
3. Department of Physics & Astronomy, Macquarie University, Sydney, NSW 2109, Australia
4. Astronomy, Astrophysics and Astrophotonics Research Centre, Macquarie University, Sydney, NSW 2109, Australia
5. School of Physics, Astronomy & Mathematics, University of Hertfordshire, College Lane, Hatfield, Hertfordshire AL10 9AB, UK
6. GRANTECAN, Cuesta de San José s/n, E-38712 Breña Baja, La Palma, Spain
7. Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38200, La Laguna, Tenerife, Spain
8. Thüringer Landessternwarte, Sternwarte 5, D-07778 Tautenburg, Germany