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arXiv · 1904.05559

Highly efficient isotope separation and ion implantation of $^{163}$Ho for the ECHo project

Tom Kieck·Holger Dorrer·Christoph E. Düllmann·Vadim Gadelshin·Fabian Schneider·Klaus Wendt
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Abstract

The effective electron neutrino mass measurement at the ECHo experiment requires high purity $^{163}$Ho, which is ion implanted into detector absorbers. To meet the project specifications in efficiency and purity, the entire process chain of ionization, isotope separation, and implantation of $^{163}$Ho was optimized. A new two-step resonant laser ionization scheme was established at the $30\, kV$ magnetic mass separator RISIKO. This achieved ionization and separation efficiencies with an average of $69(5)_\textrm{stat}(4)_\textrm{sys}\,\%$ using intra-cavity frequency doubled Ti:sapphire lasers. The implantation of a $^{166\textrm{m}}$Ho impurity is suppressed about five orders of magnitude by the mass separation. A dedicated implantation stage with focusing and scanning capability enhances the geometric implantation efficiency into the ECHo detectors to $20(2)\,\%$.

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Tom Kieck, Holger Dorrer, Christoph E. Düllmann, Vadim Gadelshin, Fabian Schneider, Klaus Wendt. 2019-04-11. Highly efficient isotope separation and ion implantation of $^{163}$Ho for the ECHo project. https://doi.org/10.1016/j.nima.2019.162602

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