title: Radiation Protection Studies for Medical Particle Accelerators using Fluka Monte Carlo Code.
abstract: Radiation protection (RP) in the use of medical cyclotrons involves many aspects both in the routine use and for the decommissioning of a site. Guidelines for site planning and installation, as well as for RP assessment, are given in international documents; however, the latter typically offer analytic methods of calculation of shielding and materials activation, in approximate or idealised geometry set-ups. The availability of Monte Carlo (MC) codes with accurate up-to-date libraries for transport and interaction of neutrons and charged particles at energies below 250 MeV, together with the continuously increasing power of modern computers, makes the systematic use of simulations with realistic geometries possible, yielding equipment and site-specific evaluation of the source terms, shielding requirements and all quantities relevant to RP at the same time. In this work, the well-known FLUKA MC code was used to simulate different aspects of RP in the use of biomedical accelerators, particularly for the production of medical radioisotopes. In the context of the Young Professionals Award, held at the IRPA 14 conference, only a part of the complete work is presented. In particular, the simulation of the GE PETtrace cyclotron (16.5 MeV) installed at S. Orsola-Malpighi University Hospital evaluated the effective dose distribution around the equipment; the effective number of neutrons produced per incident proton and their spectral distribution; the activation of the structure of the cyclotron and the vault walls; the activation of the ambient air, in particular the production of 41Ar. The simulations were validated, in terms of physical and transport parameters to be used at the energy range of interest, through an extensive measurement campaign of the neutron environmental dose equivalent using a rem-counter and TLD dosemeters. The validated model was then used in the design and the licensing request of a new Positron Emission Tomography facility.
authors.affiliation: Department of Industrial Engineering, Laboratory of Montecuccolino, University of Bologna, Via dei Colli 16, 40136 Bologna, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Infantino
authors.affiliation: Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Cicoria
authors.affiliation: Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Lucconi
authors.affiliation: Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Pancaldi
authors.affiliation: Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Vichi
authors.affiliation: Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Zagni
authors.affiliation: Department of Industrial Engineering, Laboratory of Montecuccolino, University of Bologna, Via dei Colli 16, 40136 Bologna, Italy.
authors.forename: Domiziano
authors.initials: D
authors.lastname: Mostacci
authors.affiliation: Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Marengo
mesh_terms: D003198:Computer Simulation; D017357:Cyclotrons; D009010:Monte Carlo Method; D009502:Neutrons; D010315:Particle Accelerators; D011829:Radiation Dosage; D011835:Radiation Protection