Penning trap mass measurements utilizing highly charged ions as a path to benchmark isospin-symmetry breaking corrections in Rb 74

Penning trap mass measurements of neutron-deficient Rb isotopes have been performed at TRIUMF's Ion Trap for Atomic and Nuclear Science (TITAN) facility by utilizing highly charged ions (HCIs). As imperative for a new approach with significant gain in measurement precision, experimental procedures, and systematic uncertainties are discussed in detail. Among the investigated nuclides, the superallowed nuclear β emitter Rb74 will especially benefit from the advantage offered by HCI because the limited attainable precision owing to its short half-life (T1/2=65 ms) represents a challenge for conventional Penning trap mass spectrometry. Motivated by an updated QEC value for Rb74 of 10 416.8(3.9) keV and its large isospin-symmetry breaking corrections, we present a new test to benchmark the consistency between theoretical models of isospin-symmetry breaking corrections in superallowed decays, the conserved vector current hypothesis, and experimental data.