SAMOP 2023 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MS: Fachverband Massenspektrometrie

MS 6: Accelerator Mass Spectrometry II

MS 6.8: Vortrag

Donnerstag, 9. März 2023, 16:15–16:30, F128

Sample preparation for accelerator mass spectrometry (AMS) – Approach to identify potential ¹⁰Be contamination sources — •Silke Merchel^1,2, Johannes Lachner^1,2, Oscar Marchhart¹, Georg Rugel², and Alexander Wieser¹ — ¹University of Vienna, Faculty of Physics, Isotope Physics, Austria — ²Helmholtz-Zentrum Dresden-Rossendorf, Germany

In the last decades, AMS has largely improved in the direction of lower detection limits, especially for applications of ¹⁰Be/⁹Be in Earth and environmental sciences. However, potential sources of ¹⁰Be contamination while chemical sample preparation are often known but rarely identified in detail and quantified, which would be the first step to reduce these unwanted contributions. Thus, we have aimed at investigating ¹⁰Be in (a) deionised/subboiled water, (b) commercial ²⁷Al carrier solutions, (c) ⁹Be minerals and (d) cation exchange materials differently precleaned before first use. For better quantification, we have e.g., varied ²⁷Al amounts and used ²⁷Al carriers from different companies. Though, it was partially hard to distinguish in-between "single" ¹⁰Be sources and between other sources like laboratory "dust" and cross-contamination (in lab and ion source) at the <4x10⁻¹⁵ level.
To conclude, our general recommendation is to minimize the amounts of water, ion exchange materials and ²⁷Al carrier. For ultra-low-level ¹⁰Be/²⁶Al dating, subboiled water and customised Al carriers from minerals might be advantageous. The good news, cross-contamination in an AMS chemistry lab in use for >12 years – for samples orders of magnitude different in ¹⁰Be/⁹Be – is negligible.