Analysis and characterization of neutron scattering of a Linear Accelerator (LINAC) on medical applications.

A.  Lima-Flores; R.  Palomino-Merino; E.  Espinosa; V. M.  Castano; L.  Guzman-Gatica; G.  Espinosa

doi:10.15415/jnp.2017.51007

Authors

A. Lima-Flores Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Avenida San Claudio y 18 Sur, Colonia San Manuel, Ciudad Universitaria, Puebla C.P.72570, México
R. Palomino-Merino Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Avenida San Claudio y 18 Sur, Colonia San Manuel, Ciudad Universitaria, Puebla C.P.72570, México
E. Espinosa Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Avenida San Claudio y 18 Sur, Colonia San Manuel, Ciudad Universitaria, Puebla C.P.72570, México
V. M. Castano Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Santiago de Querétaro, Querétaro C.P.76230, México
L. Guzman-Gatica Servicios de Salud del Estado de Puebla, Antiguo Camino a Guadalupe Hidalgo 11350, Puebla C.P. 72490, México
G. Espinosa Instituto de Física, Universidad Nacional Autónoma de México, Circuito de la Investigación Científica, Ciudad Universitaria, México D.F. C.P.04510, México

DOI:

https://doi.org/10.15415/jnp.2017.51007

Keywords:

Neutron Scattering, Linear Accelerator (LINAC), Nuclear Track Methodology

Abstract

In several theoretical and experimental studies, the topic of the undesirable generation of photoneutrons in rooms where a linear accelerator (LINAC) operates has been discussed. When energies above 10 MeV are used to produce X-rays and give radiotherapy treatment to patients resulting in additional radiation to patients. Accordingly, an analysis and characterization of the neutron scattering distribution on different zones in a treatment room contributes to evaluate the radiological health risk to patients, technical and other workers involved in treatment. For the evaluation, a device developed at the PAD-IFUNAM formed by a CR-39 detector enclosed by two 3mm thick acrylic plates was employed. To avoid environmental contamination, the CR-39 and the acrylics plates are enclosed in a round plastic box. Sixteen of these devices were settled in different places inside the treatment room, where a linear accelerator is used. The results show a significant concentration of neutron scattering in areas near the head of irradiation. The recommendation will be to evaluate the neutron scattering concentration in all rooms that’s operates a LINAC in order to verify the radiological health risk and to mitigate the neutron scattering when concentration levels are to high like those in our case, in order to avoid unnecessary exposition to patients and personnel in general.

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