Resolving the Q_β^- Anomaly at ¹³³Te using the Canadian Penning Trap

From the masses reportend in the 2020 Atomic Mass Evaluation, one can calculateQ_β^-(¹³³Te)=2920(6) keV. However, the highest-lying ¹³³I level populated in the β decay of ¹³³Te has been observed at E_i=2935.83(15) keV, which requires an anomalous Qⁱ_β^-=-16(6) keV. With the Canadian Penning Trap mass spectrometer, we conducted precision mass measurements of ¹³³Sb, ^133g,mTe, and ^133g,mI that were produced at CARIBU at Argonne National Laboratory's ATLAS facility. Our new measurements give Q_β^-(¹³³Te)=2934.8(11) keV, a factor of five more precise, yielding Qⁱ_β=-1.0(12) keV, a 3σ shift from the previous results. This resolves this anomaly, but indicates further problems in the nuclear data.