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

@article{Kazakov2014ProspectsFM,
  title={Prospects for measuring the 229Th isomer energy using a metallic magnetic microcalorimeter☆},
  author={Georgy A. Kazakov and Viktoria Schauer and Janine Schwestka and Simon Stellmer and Johannes H. Sterba and Andreas Fleischmann and Loredana Gastaldo and A. Pabinger and Christian Enss and Thorsten Schumm},
  journal={Nuclear Instruments \& Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment},
  year={2014},
  volume={735},
  pages={229 - 239}
}
  • G. Kazakov, V. Schauer, +7 authors T. Schumm
  • Published 13 June 2013
  • Medicine, Physics
  • Nuclear Instruments & Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment
The Thorium-229 isotope features a nuclear isomer state with an extremely low energy. The currently most accepted energy value, 7.8±0.5 eV, was obtained from an indirect measurement using a NASA x-ray microcalorimeter with an instrumental resolution 26 eV. 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 29.18 keV doublet in the γ-spectrum following the α-decay of… 
Towards a precise determination of the excitation energy of the Thorium nuclear isomer using a magnetic bottle spectrometer
Abstract 229Th is the only known nucleus with an excited state that offers the possibility for a direct laser excitation using existing laser technology. Its excitation energy has been measured
Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh.
TLDR
The presented method allowed for a first direct identification of the decay of the thorium isomer, laying the foundations to study its decay properties as prerequisite for an optical control of this nuclear transition.
X-ray pumping of the 229Th nuclear clock isomer
TLDR
Active optical pumping is presented using narrow-band 29-kiloelectronvolt synchrotron radiation to resonantly excite the second excited state of 229Th, which then decays predominantly into the isomer, enabling accurate determination of the 229mTh isomer’s energy, half-life and excitation linewidth.
Energy of the 229Th nuclear clock transition
TLDR
The method combines nuclear and atomic physics measurements to advance precision metrology, and the findings are expected to facilitate the application of high-resolution laser spectroscopy on nuclei and to enable the development of a nuclear optical clock of unprecedented accuracy.
Feasibility study of internal conversion electron spectroscopy of 229mTh
Abstract.With an expected energy of 7.8(5) eV, the isomeric first excited state in 229Th exhibits the lowest excitation energy of all known nuclei. Until today, a value for the excitation energy has
The concept of laser-based conversion electron Mössbauer spectroscopy for a precise energy determination of 229mTh
Abstract229Th is the only nucleus currently under investigation for the development of a nuclear optical clock (NOC) of ultra-high accuracy. The insufficient knowledge of the first nuclear excitation
Experimental search for the low-energy nuclear transition in 229Th with undulator radiation
To search for the lowest energy nuclear isomeric transition in 229Th in solid samples, a novel adsorption technique which prepares 229Th atoms on a surface of CaF2 is developed. Adsorbed 229Th is
Recent progress in laser spectroscopy of the actinides
The interest to perform laser spectroscopy in the heaviest elements arises from the strong impact of relativistic effects, electron correlations and quantum electrodynamics on their atomic structure.
Direct detection of the 229Th nuclear clock transition
TLDR
The direct detection of this nuclear state of 229mTh is reported, which is further confirmation of the existence of the isomer and lays the foundation for precise studies of its decay parameters.
Nuclear clocks based on resonant excitation of γ-transitions
Abstract We review the ideas and concepts for a clock that is based on a radiative transition in the nucleus rather than in the electron shell. This type of clock offers advantages like an
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