THE EFFECTS of DIFFERENT RATIO for GADOLINIUM (GD) and TUNGSTEN (W) on NEUTRON CONTAMINATION CAUSED by MEDICAL LINAC COLLIMATOR

Abstract

The linear accelerators (LINACs) produce high-energy X-rays and electron beams for the treatment of cancer patients. The basis of radiation therapy is based on the interaction between substance and radiation. LINAC as External beam radiotherapy, neutron contamination is produced in electron beams of medical LINAC by the contribution of the primary and the secondary collimators are founded. Consequently, the resulting photoneutrons can easily be scattered and spread into the clinical room. Thus, it is recommended that treatment planning performed should not be ignored in the tumor volume of the patient and areas outside this volume. The contribution of the primary collimator and the secondary collimators to the neutron contamination was found to be approximately 52% and 30%, respectively. This paper’s objective is to determine the neutron dose contamination from different materials in a LINAC. The effects of using different material ratios such as Gadolinium (Gd) and Tungsten (W) in secondary collimators on neutron contamination have been investigated by using Geant4-based Architecture for Medicine-Oriented Simulations (GAMOS) and TALYS 1.95 codes.

Keywords

• Medical LINAC
• Photo-neutron
• Secondary Collimator
• Neutron Contamination
• GAMOS
• TALYS 1.95

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