A feasibility study of a H2O-moderated 252Cf source for metrology

Angela Souza Gonçalves; Fellipe Souza da Silva; Evaldo Simões da Fonseca; Karla Cristina de Souza Patrão; Walsan Wagner Pereira

doi:10.15392/2319-0612.2023.2216

Authors

Angela Souza Gonçalves Instituto de Radioproteção e Dosimetria - IRD
Fellipe Souza da Silva Instituto de Radioproteção e Dosimetria - IRD
Evaldo Simões da Fonseca Instituto de Radioproteção e Dosimetria - IRD
Karla Cristina de Souza Patrão Instituto de Radioproteção e Dosimetria - IRD
Walsan Wagner Pereira Instituto de Radioproteção e Dosimetria - IRD

DOI:

https://doi.org/10.15392/2319-0612.2023.2216

Keywords:

Neutron Metrology, Cf- 252 moderated, Monte Carlo, Bonner Spheres Spectrometry

Abstract

The new edition of ISO 8529 series reduced from 4 to 3 standard neutron reference field. Recent studies have highlighted the increasing importance of characterizing neutron source spectra at different energies to obtain appropriate fluence-to-dose-equivalent conversion coefficient. This study presents the determination of neutron energy fluency from a free and moderated ²⁵²Cf (120 µg) source placed within spheres of different diameters containing distilled water. The spectrum determination is based on both Monte Carlo simulations and experimental measurements with Bonner Sphere Spectrometer (BSS) of multiple diameters: 5.08 cm (2"), 7.62 cm (3”), 12.70 cm (5”), 20.32 cm (8”), 25.40 cm (10”), and 30.48 cm (12”). The aim was to characterize the new water-moderated spectra, obtaining reference values for operational quantities that represent realistic radiation fields for testing, calibrating, and irradiation of personal dosimetry and survey meters.

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