2008/07/03 by P. A. Vetter, Paul Vetter, R. M. Clark +9 · 1 citation
Chemistry · Physics and Astronomy · #Mass Spectrometry Techniques and Applications #Nuclear Physics and Applications #Radioactive Decay and Measurement Techniques #nucl-ex
paper · pdf · doi:10.1016/j.physletb.2008.11.004
published as Phys.Lett.B670:196-199,2008 · 12 pages (double-spaced), 6 figures
arxiv created 2008/07/03 · openalex publication_date 2008/11/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We have searched for time modulation of the electron capture decay probability of 142Pm in an attempt to confirm a recent claim from a group at the Gesellschaft für Schwerionenforschung (GSI). We produced 142Pm via the 124Sn(23Na, 5n)142Pm reaction at the Berkeley 88-Inch Cyclotron with a bombardment time short compared to the reported modulation period. Isotope selection by the Berkeley Gas-filled Separator is followed by implantation and a long period of monitoring the 142Nd Kα x-rays from the daughter. The decay time spectrum of the x-rays is well-described by a simple exponential and the measured half-life of 40.68(53) seconds is consistent with the accepted value. We observed no oscillatory modulation at the proposed frequency at a level 31 times smaller than that reported by Litvinov \it et al. (Phys. Lett. B 664 (2008) 162; arXiv:0801.2079 [nucl-ex]). A literature search for previous experiments that might have been sensitive to the reported modulation uncovered another example in 142Eu electron-capture decay. A reanalysis of the published data shows no oscillatory behavior.