Data required for the determination of the absolute air kerma rate for (60)Co and (137)Cs gamma-rays using spherical cavity chambers were calculated using the EGS4 Monte Carlo system. Mass energy-absorption coefficient ratio and the stopping power ratio were calculated for a 10 cm(3) primary standard graphite-walled ionization chamber from the unfolded energy pulse height distributions of (60)C...

The Monte Carlo simulations using the mathematical phantom of a human body model is useful as a method of getting to know the details of the radiation exposure in a human body. However, it is very difficult to evaluate experimentally the validity of the calculation result of the simulation using the human body model. Then, the mathematical phantom of voxel-type (voxel phantom) for the Monte Car...

We report on the use of the EGS4/BEAM Monte Carlo technique to predict the output factors for clinically relevant, irregularly shaped inserts as they intercept a linear accelerator's electron beams. The output factor for a particular combination--energy, cone, insert, and source-to-surface distance (SSD)--is defined in accordance with AAPM TG-25 as the product of cone correction factor and inse...

Background: Stereotactic radiosurgery is an important clinical tool for the treatment of small lesions in the brain, including benign conditions, malignant and localized metastatic tumors. A dosimetry study was performed for Elekta ‘Synergy S ’ as a dedicated Stereotactic radiosurgery unit, capable of generating circular radiation fields with diameters of 1-5 cm at isocentre using the BEAM/EGS4...

اندازه‌گیری پرتو گاما در زمینه‌های مختلف تحقیقاتی نیازمند آشکارسازهای کارآمد است. زمینه دزیمتری فوتون آشکارساز جرقه‌ای NaI(Tl) به عنوان یکی از سوسوزن معدنی (غیرآلی)، علت دارا بودن مقدار بالای نور خروجی بسیار حایز اهمیت این پژوهش سعی گردیده است، با کمک کد مونت‌کارلو (MCNPX) مقدمات مشخصه‌یابی توسط و بهره‌گیری روش‌های متفاوت محاسبه دز (تالی‌های 6F، 4*F، 6+F 8*F) انجام شود. طور معمول، یک تابش (شمار...

background: stereotactic radiosurgery is an important clinical tool for the treatment of small lesions in the brain, including benign conditions, malignant and localized metastatic tumors. a dosimetry study was performed for elekta ‘synergy s ’ as a dedicated stereotactic radiosurgery unit, capable of generating circular radiation fields with diameters of 1-5 cm at isocentre using the beam/egs4...