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arXiv · 1301.2693

Elemental characterization of the Avogadro silicon crystal WASO 04 by neutron activation analysis

Giancarlo D'Agostino·Luigi Bergamaschi·Laura Giordani·Giovanni Mana·Enrico Massa·Massimo Oddone
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Abstract

Analytical measurements of the 28Si crystal used for the determination of the Avogadro constant are essential to prevent biased results or under-estimated uncertainties. A review of the existing data confirms the high-purity of silicon with respect to a large number of elements. In order to obtain a direct evidence of purity, we developed a relative analytical method based on neutron activation. As a preliminary test, this method was applied to a sample of the Avogadro crystal WASO 04. The investigation concerned twenty-nine elements. The mass fraction of Au was quantified to be 1.03(18) x 10-12. For the remaining twenty-eight elements, the mass fractions are below the detection limits, which range between 1 x 10-12 and 1 x 10-5.

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Giancarlo D'Agostino, Luigi Bergamaschi, Laura Giordani, Giovanni Mana, Enrico Massa, Massimo Oddone. 2013-01-12. Elemental characterization of the Avogadro silicon crystal WASO 04 by neutron activation analysis. https://doi.org/10.1088/0026-1394/49/6/696

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