1. Department of Physics, Engineering Physics and Astronomy, Queen’s University, 64 Bader lane, Kingston, K7L 3N6, ON Canada
2. Department of Physics and Space Science, Royal Military College of Canada, PO Box 17000, Stn Forces, Kingston, K7K 7B4, ON, Canada
3. Groupe d’Astrophysique des Hautes Énergies, Institut d’Astrophysique et de Géophysique Department AGO, Université de Liège, Allée du 6 Août 19c B5c, 4000 Sart Tilman, Belgium
4. LMU München, Universitätssternwarte Scheinerstr. 1, D-81679 München, Germany
5. Armagh Observatory and Planetarium, College Hill, Armagh BT61 9DG, U.K
6. Astronomical Observatory, University of Warsaw, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland