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arXiv · 2004.02571

Alpha spectrometric characterization of thin $^{233}$U sources for $^{229\text{(m)}}$Th production

Raphael Haas·Michelle Hufnagel·Roman Abrosimov·Christoph E. Düllmann·Dominik Krupp·Christoph Mokry·Dennis Renisch·Jörg Runke·Ulrich W. Scherer
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Abstract

Four different techniques were applied for the production of $^{233}$U alpha recoil ion sources, providing $^{229}$Th ions. They were compared with respect to a minimum energy spread of the $^{229}$Th recoil ions, using the emitted alpha particles as an indicator. The techniques of Molecular Plating, Drop-on-Demand inkjet printing, chelation from dilute nitric acid solution on chemically functionalized silicon surfaces, and self-adsorption on passivated titanium surfaces were used. All fabricated sources were characterized by using alpha spectrometry, radiographic imaging, and scanning electron microscopy. A direct validation for the estimated recoil ion rate was obtained by collecting $^{228}$Th recoil ions from $^{232}$U recoil ion sources prepared by self-adsorption and Molecular Plating. The chelation and the self-adsorption based approaches appear most promising for the preparation of recoil ion sources delivering monochromatic recoil ions.

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Raphael Haas, Michelle Hufnagel, Roman Abrosimov, Christoph E. Düllmann, Dominik Krupp, Christoph Mokry, Dennis Renisch, Jörg Runke, Ulrich W. Scherer. 2020-04-06. Alpha spectrometric characterization of thin $^{233}$U sources for $^{229\text{(m)}}$Th production. https://doi.org/10.1515/ract-2020-0032

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