Determination of the gamma and X-ray emission intensities of erbium-169

Zeynep Talip; Frédéric Juget; Jiri Ulrich; Youcef Nedjadi; Thierry Buchillier; M Teresa Durán; François Bochud; Claude Bailat; Nicholas P van der Meulen

doi:10.1016/j.apradiso.2021.109823

Determination of the gamma and X-ray emission intensities of erbium-169

Appl Radiat Isot. 2021 Oct:176:109823. doi: 10.1016/j.apradiso.2021.109823. Epub 2021 Jun 16.

Authors

Zeynep Talip¹, Frédéric Juget², Jiri Ulrich³, Youcef Nedjadi², Thierry Buchillier², M Teresa Durán², François Bochud², Claude Bailat², Nicholas P van der Meulen⁴

Affiliations

¹ Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland. Electronic address: zeynep.talip@psi.ch.
² Institute of Radiation Physics, Lausanne, Switzerland.
³ Laboratory of Radiochemistry, Paul Scherrer Institute, Villigen-PSI, Switzerland.
⁴ Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland; Laboratory of Radiochemistry, Paul Scherrer Institute, Villigen-PSI, Switzerland.

PMID: 34175545
DOI: 10.1016/j.apradiso.2021.109823

Abstract

The gamma and X-ray emission intensities of ¹⁶⁹Er were determined using radionuclidically pure ¹⁶⁹Er. The activity of the ¹⁶⁹Er source was standardized by the triple-to-double-coincidence ratio technique. Three independent measurements were performed to measure the emission intensities using calibrated high-purity germanium spectrometers. The efficiencies were computed with the Monte Carlo method and validated using several experimental measurements. Final results present a large uncertainty reduction compared to previous evaluations. The emission intensities per decay of ¹⁶⁹Er are reported as 1.401(40).10^-5 for the 109.8 keV line and 1.513(19).10^-6 for the 118.2 keV line. The values obtained for the X-ray lines show large discrepancies with the reference values.

Keywords: Erbium-169; Gamma-ray emission intensity; Gamma-ray spectrometry; Standardization; X-ray emission intensity.