Monte carlo Radiation Therapy lab
Objective and Background
The objective of this experiment is to determine how the numbers of simulated particles, inhomogenities in the medium and the voxel size affect the simulations ability to calculate dose, as well as to understand the effects of cutoff energy on the Monte Carlo simulation (MC). Particle interactions are the cause of everything we know to exist, such as the bright lights that illuminate the room you are in or the heat you feel when you stay in the sun for too long. To understand how these particle interactions occur we need to be able to simulate how they occur and study their effects with matter.
Monte Carlo is a mathematical method to solving real world problems using probability; it can be used to determine the most probable trajectory that individual particles will take after taking into account for the physical properties that govern the process (1). In this experiment Monte Carlo will be subjected to several different parameters to determine how these factors will affect real world particles.
EGS (Electron Gamma Shower) code will be used to do the MC simulation, it is capable of producing simulations with photons and electrons on media with various geometries; this will allow us to observe the effects of the homogeneity of the media on the Monte Carlo simulation. The user code DOSRZnrc will be used to determine the does deposited by the photons and electrons in a cylindrical geometry.
Procedure and Observations
Part 1a):
In the first part of the experiment the EGS code was configured to calculate the influence of voxel size and the number of photons on the amount of radiation dose deposited on a water phantom. A mono-energetic source of 2MeV with a radius of 2cm was chosen to be the particle beam. A trial with 1million particles incident on a water phantom at a voxel resolution of 1cm was simulated then another trial with a 5mm resolution was conducted right after. The
The objective of this experiment is to determine how the numbers of simulated particles, inhomogenities in the medium and the voxel size affect the simulations ability to calculate dose, as well as to understand the effects of cutoff energy on the Monte Carlo simulation (MC). Particle interactions are the cause of everything we know to exist, such as the bright lights that illuminate the room you are in or the heat you feel when you stay in the sun for too long. To understand how these particle interactions occur we need to be able to simulate how they occur and study their effects with matter.
Monte Carlo is a mathematical method to solving real world problems using probability; it can be used to determine the most probable trajectory that individual particles will take after taking into account for the physical properties that govern the process (1). In this experiment Monte Carlo will be subjected to several different parameters to determine how these factors will affect real world particles.
EGS (Electron Gamma Shower) code will be used to do the MC simulation, it is capable of producing simulations with photons and electrons on media with various geometries; this will allow us to observe the effects of the homogeneity of the media on the Monte Carlo simulation. The user code DOSRZnrc will be used to determine the does deposited by the photons and electrons in a cylindrical geometry.
Procedure and Observations
Part 1a):
In the first part of the experiment the EGS code was configured to calculate the influence of voxel size and the number of photons on the amount of radiation dose deposited on a water phantom. A mono-energetic source of 2MeV with a radius of 2cm was chosen to be the particle beam. A trial with 1million particles incident on a water phantom at a voxel resolution of 1cm was simulated then another trial with a 5mm resolution was conducted right after. The