1. Department of Astronomy and Space Sciences, Ege University, 35100 Bornova, İzmir, Turkey
2. Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching, Germany
3. Middle East Technical University, Department of Physics, Dumlupınar Bulvarı Universiteler Mah. No.1, 06800 Ankara,Turkey