Neutron H*(10) estimation and measurements around 18MV linac
Pablo Víctor Cerón Ramírez1, José Antonio Irán Díaz Góngora1, Lydia Concepción Paredes Gutiérrez2
1Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología, Avanzada Legaria, Calzada Legaria No. 694, 11500, México.
Summary
This study estimated neutron radiation doses in a linear accelerator treatment room using thermoluminescent dosimetry and Monte Carlo simulations. Findings help optimize radiation safety protocols for medical linear accelerators.
Area of Science:
- Medical Physics
- Radiation Dosimetry
- Nuclear Engineering
Background:
- High-energy medical linear accelerators (LINACs) generate neutron radiation, posing a safety concern in treatment rooms.
- Accurate estimation of neutron dose is crucial for radiation protection and adherence to safety standards like NCRP 151.
Purpose of the Study:
- To estimate the neutron radiation dose within an 18MV linear electron accelerator treatment room.
- To validate Monte Carlo simulation results with experimental measurements for neutron dosimetry.
Main Methods:
- Thermoluminescent dosimetry (TLD) using TLD 600 and TLD 700 pairs within paraffin spheres to measure ambient neutron dose.
- Application of NCRP 151 equations for dosimetric quantity calculation based on TLD measurements.
- Monte Carlo MCNPX code simulations to model photoneutron production from the LINAC head, considering its geometry and composition.
Main Results:
- Experimental measurements provided data for applying NCRP 151 equations to determine neutron dose.
- MCNPX simulations successfully modeled photoneutron generation, correlating with experimental conditions.
- Combined dosimetry methods offered a comprehensive assessment of neutron radiation levels.
Conclusions:
- Thermoluminescent dosimetry and Monte Carlo calculations are effective tools for assessing neutron radiation in LINAC rooms.
- The study provides valuable data for enhancing radiation safety and shielding design for medical accelerators.
- Accurate neutron dose estimation is essential for protecting staff and patients from potential radiation hazards.
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