Penning trap mass measurements utilizing highly charged ions as a path to benchmark isospin-symmetry breaking corrections inRb74

Abstract

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 $\ensuremath{\beta}$ emitter $^{74}\mathrm{Rb}$ will especially benefit from the advantage offered by HCI because the limited attainable precision owing to its short half-life $({T}_{1/2}=65$ ms) represents a challenge for conventional Penning trap mass spectrometry. Motivated by an updated ${Q}_{\mathrm{EC}}$ value for $^{74}\mathrm{Rb}$ 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.