title: Output factors for fields defined by four independent collimators.
authors.affiliation: Cross Cancer Institute, Edmonton, Alberta, Canada.
authors.forename: B
authors.initials: B
authors.lastname: Murray
authors.forename: B
authors.initials: B
authors.lastname: McClean
authors.forename: C
authors.initials: C
authors.lastname: Field
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D006801:Humans; D008961:Models, Structural; D009369:Neoplasms / Q000532:radiotherapy; D010315:Particle Accelerators; D017785:Photons; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D012542:Scattering, Radiation