cea-03736184
https://cea.hal.science/cea-03736184
https://cea.hal.science/cea-03736184/document
https://cea.hal.science/cea-03736184/file/k40_lsc_draft_v_10_revised.pdf
doi:10.1016/j.apradiso.2022.110362
[CEA] CEA - Commissariat à l'énergie atomique
[DRT] Direction de la recherche technologique
[CEA-UPSAY] CEA - Université Paris-Saclay
[UNIV-PARIS-SACLAY] Université Paris-Saclay
[LIST] Laboratoire d'Intégration des Systèmes et des Technologies
[DM2I] Département Métrologie Instrumentation & Information
[UNIVERSITE-PARIS-SACLAY] Université Paris-Saclay
[GS-ENGINEERING] Graduate School Sciences de l'Ingénierie et des Systèmes
[GS-COMPUTER-SCIENCE] Graduate School Computer Science
[MAP-CEA] MAP-contributeur
[DIN] Département d'Instrumentation Numérique
Activity standardization of two enriched 40K solutions for the determination of decay scheme parameters and the half-life
Kossert, Karsten
Amelin, Yuri
Arnold, Dirk
Merle, Renaud
Mougeot, Xavier
Schmiedel, Michael
Zapata Garcia, Daniel
[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex]
ART
40K
activity standardization
liquid scintillation counting
TDCR
CIEMAT/NIST efficiency tracing
branching ratio
metrology
ionizing radiation
radioactivity
spectrometry
Decay data measurement
gamma spectrometry
beta-rays
In this paper we describe experiments on two enriched 40K solutions to accurately determine decay data. The first solution was measured in 2004/2005 by means of a gamma-ray spectrometer with low background and a liquid scintillation (LS) counter to apply the CIEMAT/NIST efficiency tracing method. A combination of results yields an emission probability of the 1461 keV gamma-rays of Pg=0.1030(11) which is lower than current results of data evaluations.The activity concentration of the second solution was also determined by means of LS counting, but here, the CIEMAT/NIST efficiency tracing method as well as the TDCR method were applied. Again, the result was combined with that of independent gamma-ray spectrometry and the gamma-ray emission probability was found to be Pg=0.1029(9) in good agreement with the result obtained from the first solution. A combination of both experiments yields Pg=0.1029(9). The spectra of a TriCarb LS counter were carefully analyzed and a beta minus emission probability Pb- =0.8954(14) was determined. The new results for Pg and Pb- indicate that the overall probability of the decay via electron capture in recent data evaluations is overestimated.The LS counting efficiencies were computed with a stochastic model and up-to-date calculations of the beta spectrum and fractional electron-capture probabilities were used. The final activity result of the second solution is combined with the outcome of a comprehensive isotopic analysis to determine the half-life of 40K which is found to be 1.2536(27) 10^9 years.
2022-10
2024-10-01
en
Applied Radiation and Isotopes
Elsevier