Precise Q value measurements of $^{112,113}$Ag and $^{115}$Cd with the Canadian Penning trap for evaluation of potential ultra-low Q value $\beta$-decays

Understand

An ultra-low Q value $\beta$-decay can occur from a parent nuclide to an excited state in the daughter with $Q_{UL}$ <1 keV.

• These decays are of interest for nuclear $\beta$-decay theory and as potential candidates in neutrino mass determination experiments.
• To date, only one ultra-low Q value $\beta$-decay has been observed -- that of $^{115}$In with $Q_\beta$ = 147(10) eV.
• A number of other potential candidates exist, but improved mass measurements are necessary to determine if the decays are energetically allowed and, in fact, ultra-low.