ePOSTER | ||
Theme: Medical Physics |
Abstract Title | ||
Modelling of some inorganic scintillators for accurate dosemetry measurement |
Authors: | Hossam Donya | Institutions: | King Abdul Aziz University |
Monte Carlo (MC) techniques play a fundamental role in science and technology [1]. We succeeded to run some international codes on AZIZ supercomputer of KAU. These codes are MCNP6 and PENELOPE. A two non-water-equivalent of different media were used to evaluate the dose in water. For such purpose, Lu2SiO5 (LSO) and Y2SiO5 (YSO) Orthosilicates scintillators are choose for MC simulation using Penelope code. To get higher efficiency in dose calculation, variance reduction techniques are discussed. Overall results of this investigation ensured that the LSO/YSO bi-media a good combination to tackle over-response issue in dynamic photon radiotherapy. The results are interested and could be implemented for dosimetry field. Figure 1 showed the total energy deposition resulted using MC modified code with high efficient results of statistical uncertainty of is about 1%. .
Investigation of variance reduction technique was used for accurate and efficient dose calculations. Validation of the modified MC code based on correlated sampling (one of the most effective variance reduction technique) to predict absorbed photon dose of two different crystals was achieved and showed low statistical (see Fig. 4). The absorbed dose of each crystal was calculated for different depths varied 2 cm up-to 25 cm under water surface. Results of LSO crystal showed a higher dose response compared to the YSO crystals due to density effect of the different two crystals (ρLSO=7.4 g/cm3 ρYSO=4.4 g/cm3 ). Overall results are crucial and effective in radiotherapy field.
The author is aknowelge the support from AZIZ supercomputer at King abdulaziz university, Jeddah.
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