Phys.Rev. C 101, 045501 (2020)

V.E.Iacob, J.C.Hardy, H.I.Park, M.Bencomo, L.Chen, V.Horvat, N.Nica, B.T.Roeder, A.Saastamoinen, I.S.Towner

Precise β branching-ratio measurement for the 0⁺ → 0⁺ superallowed decay of ³⁴Ar

RADIOACTIVITY ³⁴Ar(β⁺), (EC)[from ¹H(³⁵Cl, 2n), E=30 MeV/nucleon, followed by separation of fully stripped reaction ejectiles using the MARS spectrometer at the K500 superconducting cyclotron at Texas A and M University]; measured Eβ⁺, Iβ⁺, Eγ, Iγ, β⁺γ-coin. ³⁴Cl; deduced levels, J, π, β-branching ratio, EC to β⁺ emission ratios, logft, superallowed 0+ to 0+ β transition, isospin-symmetry-breaking correction, ratios of ft values for the mirror pair of superallowed transitions ³⁴Ar to ³⁴Cl and ³⁴Cl to ³⁴S. Comparison with previous experimental data, and with shell model calculations with Woods-Saxon radial wave functions. Systematics of logft ratios in A=26, 34, 38 and 42 mirror pairs. Relevance to up-down quark-mixing element V_ud of the Cabibbo-Kobayashi-Maskawa matrix.

doi: 10.1103/PhysRevC.101.045501