Prospects for measuring the 229Th isomer energy using a metallic magnetic microcalorimeter

• Verfasst von: Kazakov, G. A. [VerfasserIn]
• Verfasst von: Schauer, V. [VerfasserIn]
• Verfasst von: Schwestka, J. [VerfasserIn]
• Verfasst von: Stellmer, S. P. [VerfasserIn]
• Verfasst von: Sterba, J. H. [VerfasserIn]
• Verfasst von: Fleischmann, Andreas [VerfasserIn]
• Verfasst von: Gastaldo, Loredana [VerfasserIn]
• Verfasst von: Pabinger, Andreas [VerfasserIn]
• Verfasst von: Enss, Christian [VerfasserIn]
• Verfasst von: Schumm, T. [VerfasserIn]
• Titel: Prospects for measuring the 229Th isomer energy using a metallic magnetic microcalorimeter
• Verf.angabe: G.A. Kazakov, V. Schauer, J. Schwestka, S.P. Stellmer, J.H. Sterba, A. Fleischmann, L. Gastaldo, A. Pabinger, C. Enss, T. Schumm
• Jahr: 2014
• Jahr des Originals: 2013
• Umfang: 11 S.
• Fussnoten: Im Titel ist die Zahl "229" hochgestellt ; Available online 14 September 2013 ; Gesehen am 13.10.2020 ; This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, andreproduction in any medium, provided the original author and source are credi
• Titel Quelle: Enthalten in: Nuclear instruments & methods in physics research / A
• Ort Quelle: Amsterdam : North-Holland Publ. Co., 1984
• Jahr Quelle: 2014
• Band/Heft Quelle: 735(2014), Seite 229-239
• ISSN Quelle: 1872-9576
• DOI: doi:10.1016/j.nima.2013.09.012
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Design of experiment
• Sach-SW: Gamma spectroscopy
• Sach-SW: Isomer energy
• Sach-SW: Thorium-229
• K10plus-PPN: 1735421995

Abstract

The Thorium-229 isotope features a nuclear isomer state with an extremely low energy. The currently most accepted energy value, 7.8±0.5eV, was obtained from an indirect measurement using a NASA x-ray microcalorimeter with an instrumental resolution 26eV. We study, how state-of-the-art magnetic metallic microcalorimeters with an energy resolution down to a few eV can be used to measure the isomer energy. In particular, resolving the 29.18keV doublet in the γ-spectrum following the α-decay of Uranium-233, corresponding to the decay into the ground and isomer state, allows to measure the isomer transition energy without additional theoretical input parameters, and increase the energy accuracy. We study the possibility of resolving the 29.18keV line as a doublet and the dependence of the attainable precision of the energy measurement on the signal and background count rates and the instrumental resolution.