title: Determination of the neutron and photon spectra of a clinical fast neutron beam.
abstract: A simple technique to determine the neutron and photon spectra of a clinical fast neutron beam is described. This technique involves making narrow beam attenuation measurements with a pair of ionization chambers and an iterative fitting program to analyze the data. A method is also described for determining the first-guess neutron spectrum for input into the iterative program. The results of the analysis yield spectra suitable for use in dose calculation algorithms and dosimetry protocols. Presented here is the first-known published photon spectrum from a clinical machine.
authors.affiliation: Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston 77030.
authors.forename: M F
authors.initials: MF
authors.lastname: Moyers
authors.forename: J L
authors.initials: JL
authors.lastname: Horton
mesh_terms: D006801:Humans; D009502:Neutrons; D010315:Particle Accelerators; D011827:Radiation; D011874:Radiometry / Q000295:instrumentation; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy; D013679:Technology, Radiologic