  A novel method for simultaneous measurement of masses, Q-values, isomer
excitation energies, half-lives and decay branching ratios of exotic nuclei has
been demonstrated. The method includes first use of a stopping cell as an ion
trap, combining containment of precursors and decay-recoils for variable
durations in a cryogenic stopping cell (CSC), and afterwards the identification
and counting of them by a multiple-reflection time-of-flight mass spectrometer
(MR-TOF-MS). Feasibility has been established by recording the decay and growth
of $^{216}$Po and $^{212}$Pb (alpha decay) and of $^{119m2}$Sb (t$_{1/2}$ =
850$\pm$90 ms) and $^{119g}$Sb (isomer transition), obtaining half-lives and
branching ratios consistent with literature values. Hardly any
non-nuclear-decay losses have been observed in the CSC for up to $\sim$10
seconds, which exhibits its extraordinary cleanliness. For $^{119}$Sb, this is
the first direct measurement of the ground and second isomeric state masses,
resolving the discrepancies in previous excitation energy data. These results
pave the way for the measurement of branching ratios of exotic nuclei with
multiple decay channels.
