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Updated: Jul 7, 2026
10:42
Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
The decay of 133mXe
K Peräjärvi1, J Turunen, J Hakala
1STUK-Radiation and Nuclear Safety Authority, PO Box 14, Helsinki FIN-00881, Finland. kari.perajarvi@stuk.fi
Summary
This study re-measured Xenon-133m decay using advanced spectroscopy. New conversion coefficients align with theory, resolving prior experimental discrepancies for this important isotope.
Area of Science:
- Nuclear Physics
- Atomic Physics
Background:
- Previous experimental studies on Xenon-133m decay exhibited inconsistencies.
- Accurate conversion coefficients are crucial for understanding nuclear structure and decay processes.
Purpose of the Study:
- To re-measure the decay of Xenon-133m.
- To determine K and L+M+... shell conversion coefficients.
- To resolve discrepancies in previous experimental findings.
Main Methods:
- Utilized an electron-transporter spectrometer for high-precision measurements.
- Employed a planar High-Purity Germanium (HPGe) detector.
- Produced Xenon-133m samples via proton-induced fission using an on-line mass separator.
Main Results:
- Deduced K-shell conversion coefficient, alpha(Kappa)=6.5(9).
- Deduced L+M+... shell conversion coefficients, alpha(L+M+...)=2.9(4).
- Obtained values agree with theoretical predictions within uncertainty limits.
Conclusions:
- The new measurements provide accurate conversion coefficients for Xenon-133m decay.
- This resolves inconsistencies between prior experimental studies.
- The findings contribute to a better understanding of nuclear decay mechanisms.
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