On the equivalence between homogeneously prepared sources and sources prepared by seeding in layers for different geometries, energies and matrix parameters

Maria Clara Ferrari; Virginia Peyres; Nuria Navarro; Mario P Rossi; Gabriela Cerutti; Marcos Mejuto; Teresa Crespo

doi:10.1016/j.apradiso.2019.108894

On the equivalence between homogeneously prepared sources and sources prepared by seeding in layers for different geometries, energies and matrix parameters

Appl Radiat Isot. 2019 Dec:154:108894. doi: 10.1016/j.apradiso.2019.108894. Epub 2019 Sep 13.

Authors

Maria Clara Ferrari¹, Virginia Peyres², Nuria Navarro³, Mario P Rossi¹, Gabriela Cerutti¹, Marcos Mejuto³, Teresa Crespo³

Affiliations

¹ Radioisotope Metrology Laboratory (LMR), CNEA, Buenos Aires, Argentina.
² Laboratorio de Metrología de Radiaciones Ionizantes, CIEMAT, Avenida Complutense 40, 28040, Madrid, Spain. Electronic address: Virginia.peyres@ciemat.es.
³ Laboratorio de Metrología de Radiaciones Ionizantes, CIEMAT, Avenida Complutense 40, 28040, Madrid, Spain.

PMID: 31581060
DOI: 10.1016/j.apradiso.2019.108894

Abstract

Measuring the radioactive content of environmental samples requires the use of appropriate reference materials with the same composition and density as the matrices to be measured. If they are not available, ad hoc artificially spiked reference materials are an alternative. Spiking in layers requires a detailed study of the drop distribution, as energy and decay scheme of the component radionuclides must be taken into account to produce a reference material that represents, in efficiency terms, a real sample. A method based on Monte Carlo simulation has been developed to find the optimal distribution of drops in layers for the combination of two typical soil samples and four radionuclides. Results have been validated by comparison with samples prepared by two techniques: methanol bath and spiking in layers.

Keywords: Gamma-ray spectrometry; Reference material; Source preparation; Traceability.