Página 304 - irpa

304 ST 3.4 –Protección radiológica en radioterapia
SIMULATION OF A GEM GASEOUS PARTICLE DETECTOR FOR
CLINICAL DOSIMETRY
Sevilla Moreno, Andrés Camilo*; Castro Serrato, Héctor Fabio
Universidad Nacional de Colombia. Colombia.
* Responsible author, email: acsevillam@unal.edu.co
Modern radiation therapy such as intensity modulated radiation therapy (IMRT) and volumetric
modulated arc therapy (VMAT) reach high gradients and complicated dose conformation
patterns, consequently the use of these techniques require to develop high precision (to
milimetric and submilimetric scales) 2D and 3D dosimetry systems able to evaluate the
accuracy of dose delivered to the patient. Currently the value recommended by the International
Commission on Radiation Units and Measurements (ICRU) is about ±5%, however, It should be
as small as possible. The new generation of gaseous particle detectors called Micro Pattern
Gaseous Detector (MPGD) offers multiple odds in this field, particularly The Gaseous Electron
Multiplier (GEM) has been used in some non-commercial dosimeters and scanning devices
using different radiation sources in therapy energy range with successful results. In this work is
design a GEM-based dosimeter for clinical applications; using geometry and tracking (Geant4)
simulation toolkit and scientific simulation framework (SciFW1), the system performance as 2D
dosimeter to photon beam therapy is evaluated and cross checked with experimental data.