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arXiv · 1405.7524

Neutron activation analysis of the 30Si content of highly enriched 28Si: proof of concept and estimation of the achievable uncertainty

Giancarlo D'Agostino·Giovanni Mana·Massimo Oddone·Michele Prata·Luigi Bergamaschi·Laura Giordani
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Abstract

We investigated the use of neutron activation to estimate the 30Si mole fraction of the ultra-pure silicon material highly enriched in 28Si for the measurement of the Avogadro constant. Specifically, we developed a relative method based on Instrumental Neutron Activation Analysis and using a natural-Si sample as a standard. To evaluate the achievable uncertainty, we irradiated a 6 g sample of a natural-Si material and modeled experimentally the signal that would be produced by a sample of the 28Si-enriched material of similar mass and subjected to the same measurement conditions. The extrapolation of the expected uncertainty from the experimental data indicates that a measurement of the 30Si mole fraction of the 28Si-enriched material might reach a 4% relative combined standard uncertainty.

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Giancarlo D'Agostino, Giovanni Mana, Massimo Oddone, Michele Prata, Luigi Bergamaschi, Laura Giordani. 2014-05-29. Neutron activation analysis of the 30Si content of highly enriched 28Si: proof of concept and estimation of the achievable uncertainty. https://doi.org/10.1088/0026-1394/51/3/354

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