1. 1 Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Indonesia , Depok , West Java , , Indonesia
2. 2 Department of Radiation Oncology, Faculty of Medicine, Universitas Indonesia, dr. Cipto Mangunkusumo General Hospital , Jakarta , , Indonesia
3. 3 PT Elekta Medical Solution , Cowell Tower 7th Floor Unit 2A , Jakarta , , Indonesia