The β- decay of K47 to Ca47 is an appropriate mechanism for benchmarking interactions spanning the sd and pf shells, but current knowledge of the β - decay scheme is limited. We have performed a high-resolution, high-efficiency study of the β- decay of K47 with the GRIFFIN spectrometer at TRIUMF-ISAC. The study revealed 48 new transitions, a more precise value for the K47 half-life [17.38(3) s], and new spin and parity assignments for 8 excited states. Levels placed for the first time here raise the highest state observed in β- decay to within 568(3) keV of the Q value and confirm the previously measured large β - decay branching ratios to the low-lying states. Previously unobserved β- feeding to 3/2+ states between 4.5 and 6.1 MeV excitation energy was identified with a total β - feeding intensity of 1.29(2)%. The sum of the B(GT) values for these states indicates that the 1s1/2 proton hole strength near this excitation energy is comparable to the previously known 1s1/2 proton and neutron hole strengths near 2.6 MeV.
|Journal||Physical Review C|
|State||Published - Nov 11 2020|
Bibliographical noteFunding Information:
We would like to thank the operations and beam delivery staff at TRIUMF for providing the radioactive beam. J.K.S. would like to thank S. R. Stroberg, J. Henderson, J. Smallcombe, and J. R. Leslie for helpful discussions. The GRIFFIN spectrometer was jointly funded by the Canada Foundation for Innovation (CFI), TRIUMF, and the University of Guelph. TRIUMF receives federal funding via a contribution agreement through the National Research Council Canada (NRC). C.E.S. acknowledges support from the Canada Research Chairs program. This work was supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC). This material is based upon work supported by the U. S. National Science Foundation (NSF) under Grant No. PHY-1913028.
© 2020 American Physical Society.
ASJC Scopus subject areas
- Nuclear and High Energy Physics