K´et´evi A. Assamagan1*, Somi´ealo Azote2*, Simon H. Connell3, Cyrille E. Haliya4, Toivo S. Mabote5, Kondwani C.C. Mwale6, Ebode F. Onyie7, George Zimba8
1Brookhaven National Laboratory, Physics Department, Upton, New York, USA.
2Universit´e de Lom´e, D´epartement de Physique, Lom´e, Togo.
3University of Johannesburg, Johannesburg, South Africa.
4University of Abomey-Calavi, International Chair in Mathematical Physics and Applications, Cotonou, Benin.
5Universidade Eduardo Mondlane, Grupo de Astrof´ısica e Ciˆencias Espaciais, Maputo, Mozambique.
6University of Rwanda, African Center of Excellence for Innovative Teaching and Learning Mathematics and Science, Kigali, Rwanda.
7University of Yaounde I, Department of Physics, Yaounde, Cameroon.
8University of Jyva¨skyla¨, Department of Physics, Jyva¨skyla¨, Finland.
