title: Bremsstrahlung production from a linac target in the presence of external magnetic fields.
abstract: A method to increase the photon fluence of the linac is to apply a magnetic field to the bremsstrahlung producing electrons in the target. This field changes the electron paths, and therefore the photon trajectories. In this research Monte Carlo techniques are used to model the effect of three separate magnetic field configurations applied to a tungsten target, on the forward projection of bremsstrahlung created from incident 6 MeV electrons. A radial fluence spectrum is produced for each magnetic field. The maximum increase in fluence is shown to be around 10% for a physically possible field. We conclude that the cost of constructing and installing such magnets (currently) outweighs the small increase in fluence yield.
authors.affiliation: Cancer Therapy Centre, Liverpool Hospital, New South Wales.
authors.forename: J T
authors.initials: JT
authors.lastname: Booth
authors.forename: P J
authors.initials: PJ
authors.lastname: Keall
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D004583:Electrons; D006801:Humans; D008280:Magnetics; D008962:Models, Theoretical; D009010:Monte Carlo Method; D010315:Particle Accelerators; D017785:Photons / Q000627:therapeutic use*; D011882:Radiotherapy, High-Energy