正电子发射断层扫描回旋加速器中因（13）N产生的中子能谱。

Neutron spectra due (13)N production in a PET cyclotron.

作者信息

Benavente J A, Vega-Carrillo H R, Lacerda M A S, Fonseca T C F, Faria F P, da Silva T A

机构信息

Centro de Desenvolvimento da Tecnologia Nuclear, CDTN, Av. Presidente Antonio Carlos, 6627, Pampulha, CEP: 31270-901 Belo Horizonte, MG, Brazil; Departamento de Engenharia Nuclear, Programa de Pós Graduação em Ciências e Técnicas Nucleares, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, CEP: 31270-901 Belo Horizonte, MG, Brazil.

Unidad Academica de Estudios Nucleares de la UAZ, C. Cipres, 10, 98068, Zacatecas, Mexico.

出版信息

Appl Radiat Isot. 2015 May;99:20-4. doi: 10.1016/j.apradiso.2015.01.029. Epub 2015 Feb 7.

DOI:10.1016/j.apradiso.2015.01.029

PMID:25699664

Abstract

Monte Carlo and experimental methods have been used to characterize the neutron radiation field around PET (Positron Emission Tomography) cyclotrons. In this work, the Monte Carlo code MCNPX was used to estimate the neutron spectra, the neutron fluence rates and the ambient dose equivalent (H*(10)) in seven locations around a PET cyclotron during (13)N production. In order to validate these calculations, H*(10) was measured in three sites and were compared with the calculated doses. All the spectra have two peaks, one above 0.1MeV due to the evaporation neutrons and another in the thermal region due to the room-return effects. Despite the relatively large difference between the measured and calculated H*(10) for one point, the agreement was considered good, compared with that obtained for (18)F production in a previous work.

摘要

蒙特卡罗方法和实验方法已被用于表征正电子发射断层扫描（PET）回旋加速器周围的中子辐射场。在这项工作中，蒙特卡罗代码MCNPX被用于估算在生产（13）N期间PET回旋加速器周围七个位置的中子能谱、中子注量率和环境剂量当量（H*(10)）。为了验证这些计算结果，在三个位置测量了H*(10)，并与计算剂量进行了比较。所有能谱都有两个峰值，一个在0.1MeV以上，归因于蒸发中子，另一个在热区，归因于房间返回效应。尽管在一个点上测量的和计算的H*(10)之间存在相对较大的差异，但与先前工作中生产（18）F时获得的结果相比，一致性被认为是良好的。