title: Backscattered radiation into a transmission ionization chamber: measurement and Monte Carlo simulation.
abstract: Backscattered radiation (BSR) from field-defining collimators can affect the response of a monitor chamber in X-radiation fields. This contribution must be considered since this kind of chamber is used to monitor the equipment response. In this work, the dependence of a transmission ionization chamber response on the aperture diameter of the collimators was studied experimentally and using a Monte Carlo (MC) technique. According to the results, the BSR increases the chamber response of over 4.0% in the case of a totally closed collimator and 50 kV energy beam, using both techniques. The results from Monte Carlo simulation confirm the validity of the simulated geometry.
authors.affiliation: Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN), Comissão Nacional de Energia Nuclear, São Paulo, SP, Brazil. mairaty@ipen.br
authors.forename: Maíra T
authors.initials: MT
authors.lastname: Yoshizumi
authors.forename: Hélio
authors.initials: H
authors.lastname: Yoriyaz
authors.forename: Linda V E
authors.initials: LV
authors.lastname: Caldas
mesh_terms: D016477:Artifacts; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009010:Monte Carlo Method; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity