The shape of the radiation source of a linac has a direct impact on the delivered dose distributions, especially in the case of small radiation fields. Traditionally, a single Gaussian source model is used to describe the electron beam hitting the target, although different studies have shown that the shape of the electron source can be better described by a mixed distribution consisting of two...

Objective: Modelling linear accelerator (linac) photon beams using the Monte Carlo (MC) technique is presently most precise with which to calculate radiotherapy beam data. Complicated treatment plans can be achieved by Agility multileaf collimator. The focus of this study model a linac, integrated an head, EGSnrc MC code and investigate its accuracy compared actual measurements. Methodology: A ...

  Introduction: Several studies have discussed to the electron contamination caused by the air column between the head of linac and patient for photon beams. Since it is not possible to measure the electron contamination with practical dosimetry, the Monte Carlo technique is an appropriate and accurate choice to calculate particle flounce in radiation therapy. The purpose of t...

Introduction: The aim of this study was to investigate the initial electron beam parameters for Monte Carlo model of 6MV photon beam produced by Siemens Oncor® linear accelerator.   Materials and Methods: In this study, the EGSnrc Monte Carlo user codes BEAMnrc and DOSXYZnrc were used. The beamnrc code were used for modelling of a 6 MV photon beam produced by...

background: understanding of the incident electron energy and angular distributions from clinical electron accelerators (linacs) is important for dosimetry and treatment planning. the most important goals of this study were to evaluate the energy fluence and angular distributions of electron beams from a neptun 10pc linac using the monte carlo (mc) code. materials and methods: the linac electro...

Introduction Superficial X-ray therapy is one of the most important treatment methods in radiotherapy especially in the treatment of superficial skin lesions (Up to 300 kVp). Quality of the X-ray beam that can be expressed by Half-Value Layer (HVL), are important indices for this type of treatment effective energy of photon and Homogeneity Coefficient (HC). Materials and Methods The HC of the s...

Introduction Superficial X-ray therapy is one of the most important treatment methods in radiotherapy especially in the treatment of superficial skin lesions (Up to 300 kVp). Quality of the X-ray beam that can be expressed by Half-Value Layer (HVL), are important indices for this type of treatment effective energy of photon and Homogeneity Coefficient (HC). Materials and Methods The HC of the s...

Stopping power ratios sw,air for electron beams produced by the NOVAC7® IORT accelerator were calculated at different depths in water by the SPRRZnrc Monte Carlo code. As input for the SPRRZnrc code a phase-space data file obtained for any beam by the BEAMnrc code was used. The calculated stopping power ratios were compared with those recommended by the IAEA dosimetry protocols TRS-381 and TRS-...

Percentage depth doses (PDDs) and transverse dose profiles (TDPs) were calculated by a Monte Carlo simulation of electron beams of different energies (3, 5, 7 and 9 MeV) produced by a NOVAC7® accelerator. The NOVAC7® is a linear accelerator designed for Intraoperative Radiation Therapy (IORT). The PDDs and TDPs were also experimentally determined. Both calculations and measurements were done on...