Skip to Main content Skip to Navigation
Journal articles

High precision measurement of the $^{151}$Sm beta decay by means of a metallic magnetic calorimeter

Karsten Kossert 1, * Martin Loidl 2 Xavier Mougeot 2 Michael Paulsen 1 Philipp Ranitzsch 1 Matias Rodrigues 2 
* Corresponding author
2 LNHB - Laboratoire National Henri Becquerel
DM2I - Département Métrologie Instrumentation & Information : DRT/LIST/DM2I
Abstract : The beta decay of $^{151}$Sm was measured by means of a metallic magnetic calorimeter. The measurement and subsequent analysis yielded a beta spectrum with an outstanding high-energy resolution of about 70 eV (FWHM) at 22 keV and a very low energy threshold well below 400 eV. The spectrum exhibited unexpectedly elevated beta emission probabilities at very low energy that we have not been able to reproduce in our theoretical study. The data analysis was thus scrutinized and an independent analysis of the same data set carried out. All new approaches have confirmed the previously found shape of the beta spectrum. The measured spectrum was compared to predictions from an advanced theoretical modeling that includes the atomic exchange effect, precise radiative corrections as well as the realistic nuclear structure that usually plays an important role in first forbidden non-unique transitions. The measured spectrum was then carefully analyzed to determine the maximum beta energy, which was found to be Q = 76.430(68) keV. The dominant beta decay of $^{151}$Sm populates the ground state of $^{151}$Eu, and a weak beta branch populates the first excited state of $^{151}$Eu. From our measurements, the probabilities of these two branches were determined to be 99.31(11)% and 0.69(11)%, respectively.
Complete list of metadata
Contributor : Contributeur MAP CEA Connect in order to contact the contributor
Submitted on : Monday, May 9, 2022 - 12:00:10 PM
Last modification on : Wednesday, May 11, 2022 - 3:15:01 AM
Long-term archiving on: : Wednesday, August 10, 2022 - 6:57:33 PM



Karsten Kossert, Martin Loidl, Xavier Mougeot, Michael Paulsen, Philipp Ranitzsch, et al.. High precision measurement of the $^{151}$Sm beta decay by means of a metallic magnetic calorimeter. Applied Radiation and Isotopes, Elsevier, 2022, 185, pp.110237. ⟨10.1016/j.apradiso.2022.110237⟩. ⟨cea-03662368⟩



Record views


Files downloads