1. Imperial College London, Blackett Laboratory, Prince Consort Road, London, SW7 2AZ, UK
2. RAL Space, CCLRC, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK
3. School of Physical Sciences, The Open University, Milton Keynes, MK7 6AA, UK
4. Oxford Astrophysics, Denys Wilkinson Building, University of Oxford, Keble Road, Oxford OX1 3RH, UK
5. Instituto de Astrofísica e Ciências do Espaço, Universidade de Lisboa, OAL, Tapada da Ajuda, PT1349-018 Lisboa, Portugal
6. Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Edifício C8, Campo Grande, PT1749-016 Lisbon, Portugal
7. Université Paris Diderot, AIM, Sorbonne Paris Cité, CEA, CNRS, F-91191 Gif-sur-Yvette, France
8. IRFU, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France
9. Department of Physics, Virginia Tech, Blacksburg, VA 24061, USA
10. School of Sciences, European University Cyprus, Diogenes Street, Engomi, 1516, Nicosia, Cyprus
11. SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD, Groningen, the Netherlands
12. Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV, Groningen, the Netherlands