1. Physics Department, Faculty of Science; Taif University; Taif Saudi Arabia
2. Physics Department, Faculty of Science; Cairo University; Cairo Egypt
3. Physics Department, Faculty of Science and Arts, P.O. Box 80200, Code 21589 Khulais, University of Jeddah; Saudi Arabia
4. Physics Department, Faculty of Science, Al-Azhar University, P.O. 71452; Assiut - Egypt