http://careers-carrieres.nrc-cnrc.gc.ca/careers/jobpost.nsf/PostByCityE

AAPM is the American Association of Physicists in Medicine http://www.aapm.org

Monte Carlo (MC) studies of the output of medical linear accelerators have demonstrated that in-air profiles are useful in the beam commissioning process. A recent investigation of x-ray profiles (Tonkopi et al, Med. Phys 32 (9), 2005) showed very good agreement between measurement and EGSnrc calculations but to achieve this level of agreement the beam linac spot size, energy and angular divergence had to be treated as variables. In this project

Purpose: The EGSnrc Monte Carlo code was benchmarked against newly measured angular scattering distributions of electron beams through thin materials. Method and Materials: The BEAMnrc user code was used for the simulation of the experimental setup. The geometry, beam and material properties were implemented in BEAMnrc, while the DOSXYZnrc user code was used to score the absorbed dose up to angles of 10°. The electron beam was generated using the

To model the transport of electrons through material requires knowledge of how the electrons lose energy and scatter. Theoretical models are used to describe electron energy loss and scatter and these models are supported by a limited amount of measured data. The purpose of this work was to obtain additional data that can be used to test models of electron scattering. Measurements were carried out using 13 and 20 MeV pencil beams of electrons produced