Affiliation: | 1.Department of Physics, Faculty of Science, King Khalid University, Abha, Saudi Arabia ;2.Department of Physics, Faculty of Science, New-Valley University, El-Kharga, New-Valley, Egypt ;3.Physics Department, Al-Azhar University, Assiut, Egypt ;4.Department of Physics, Faculty of Science, Aswan University, Aswan, Egypt ;5.Physics Department, Faculty of Science, Taibah University, Medina, Saudi Arabia ;6.Physics Department, Faculty of Science, Sohag University, Sohag, Egypt ; |