Neutron calibration field at Institute for Nuclear Science and Technology

Le Ngoc Thiem1, Nguyen Ngoc Quynh1, Ho Quang Tuan1, Trinh Van Giap1, Nguyen Tuan Khai1, Nguyen Huu Quyet1
1 Institute for Nuclear Science and Technology

Main Article Content

Abstract

In this study, a neutron calibration field of a 241Am-Be standard source at the Institute for Nuclear Science and Technology is characterized in terms of neutron spectral fluxes and neutron ambient dose equivalent ( ) rates based on ISO 8529 recommended generalized fit method together with measurements using a Bonner Sphere Spectrometer and MAXED unfolding techniques. The total, direct and scattered neutron components as well as rates and neutron spectral fluxes are separated from each other. The direct  rates and neutron spectral fluxes in the free field as functions of distances from the source are also theoretically calculated based on the neutron source strength. The comparison between experimental data and theoretical calculations of the  rates and neutron spectral fluxes shows good agreement within 3%, this has confirmed the reliability of the field characterization process and its applicability in the practical calibration works for neutron survey meters.

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References

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