1. Atomic and Molecular Physics Lab, Department of Physics, University of Rajshahi, Rajshahi, Bangladesh
2. Department of General Educational Development, Daffodil International University, Dhaka, Bangladesh
3. Division of Radiation Protection and Safety Control, Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan
4. Department of Physics, Florida A&M University, Tallahassee, FL, USA