title: Improving the neutron-to-photon discrimination capability of detectors used for neutron dosimetry in high energy photon beam radiotherapy.
abstract: The increasing interest of the medical community to radioinduced second malignancies due to photoneutrons in patients undergoing high-energy radiotherapy, has stimulated in recent years the study of peripheral doses, including the development of some dedicated active detectors. Although these devices are designed to respond to neutrons only, their parasitic photon response is usually not identically zero and anisotropic. The impact of these facts on measurement accuracy can be important, especially in points close to the photon field-edge. A simple method to estimate the photon contribution to detector readings is to cover it with a thermal neutron absorber with reduced secondary photon emission, such as a borated rubber. This technique was applied to the TNRD (Thermal Neutron Rate Detector), recently validated for thermal neutron measurements in high-energy photon radiotherapy. The positive results, together with the accessibility of the method, encourage its application to other detectors and different clinical scenarios.
authors.affiliation: Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Spain; Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Irazola
authors.affiliation: Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Spain; Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Terrón
authors.affiliation: Politecnico di Milano, Dipartimento di Ingegneria Nuclear, Milano, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Bedogni
authors.affiliation: Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare (INFN), Italy.
authors.forename: A
authors.initials: A
authors.lastname: Pola
authors.affiliation: Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare (INFN), Italy.
authors.forename: M
authors.initials: M
authors.lastname: Lorenzoli
authors.affiliation: Instituto de Física, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: B
authors.initials: B
authors.lastname: Sánchez-Nieto
authors.affiliation: Departamento de Física de Partículas, Universidad de Santiago, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Gómez
authors.affiliation: Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Spain; Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Sánchez-Doblado
mesh_terms: D006801:Humans; D009502:Neutrons; D017785:Photons; D011874:Radiometry; D011882:Radiotherapy, High-Energy
keywords: Neutron-to-photon discrimination; Peripheral doses in radiotherapy; Second cancer risk; Thermal neutron detector