Investigación

 

Características dosimétricas de fuentes isotópicas de neutrones

 

H.R. Vega-Carrillo^a,b,c, E. Manzanares Acuña^a, V.M. Hernández Dávila^a,b, G.A. Mercado Sánchez^c, E. Gallego Díaz^d y A. Lorente Fillol^d

 

^a Estudios Nucleares; Universidad Autónoma de Zacatecas,Apdo. Postal 336, 98000 Zacatecas, Zac. México e-mail: fermineutron@yahoo.com

^b Ing. Eléctrica; Universidad Autónoma de Zacatecas,Apdo. Postal 336, 98000 Zacatecas, Zac. México e-mail: fermineutron@yahoo.com

^c Matemáticas; Universidad Autónoma de Zacatecas,Apdo. Postal 336, 98000 Zacatecas, Zac. México e-mail: fermineutron@yahoo.com

^d Departamento de Ingeniería Nuclear Universidad Politécnica de Madrid C/José Gutiérrez Abascal 2, E-28006 Madrid, España, e-mail: eduardo.gallego@upm.es

 

Recibido el 8 de marzo de 2005.
Aceptado el 4 de julio de 2005.

 

Resumen

Mediante metodos Monte Carlo se han calculado los espectros de los neutrones producidos por ²⁵²Cf, ²⁵²Cf/D₂O, ²⁴¹AmBe, ²³⁹PuBe, ¹⁴⁰LaBe, ²³⁹Pu¹⁸O₂ y ²²⁶RaBe. Con la información del espectro se calculó la energía promedio de los neutrones de cada fuente. Mediante los coeficientes de fluencia a dosis se determinaron, para cada una de las fuentes estudiadas, los factores de fluencia a dosis. Las dosis calculadas fueron H, H*(10), H_p,slab (10,0°), E_AP y E_ISO. Para los cálculos, las fuentes se modelaron como puntuales y sus características se determinaron en el vacío. Además, para el caso de las fuentes de ²³⁹PuBe y ²⁴¹AmBe, se realizaron cálculos Monte Carlo modelando las fuentes con sus dimensiones, y las propiedades dosimétricas se determinaron en un espacio lleno de aire. Los resultados de esta última fase de cálculos se compararon con los resultados experimentales obtenidos para ambas fuentes.

Descriptores: Fuentes de neutrones; Monte Carlo; dosimetría.

 

Abstract

Using Monte Carlo methods, the neutron spectra produced by ²⁵²Cf, ²⁵²Cf/D₂O, ²⁴¹AmBe, ²³⁹PuBe, ¹⁴⁰LaBe, ²³⁹Pu¹⁸O₂ and ²²⁶RaBe were calculated. The mean energy and the dosimetric features for each source were determined. The calculated dose were H, H*(10), H_p,slab (10,0°), E_AP y E_ISO. During calculations the sources were modeled as point-like and the dosimetric features were determined in vacuum. For ²³⁹PuBe and ²⁴¹AmBe neutron sources the Monte Carlo calculations were carried out using the actual dimensions and their dosimetric characteristics were evaluated inside of an air-filled region. These results were compared with experimental data.

Keywords: Neutron sources; Monte Carlo; dosimetry.

 

PACS: 29.25.Dz; 24.10.i.x; 28.20.Gd

 

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Agradecimientos

Este trabajo fue parcialmente apoyado por el CONACyT bajo el convenio SEP-2004-C01-46893

 

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