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A high-statistics \(\beta \)-decay experiment was conducted at the TRIUMF-ISAC facility using the \(8\pi \) \(\gamma \)-ray spectrometer and its ancillary detectors to study the low-spin structure of \(^{98}\)Zr. The analysis of \(\gamma \)–\(\gamma \) and \(e^-\)–\(\gamma \) coincidence data is presented. New measurements of \(\gamma \)-ray branching ratios and mixing ratios are reported for four \(J^{\pi } = 2^+\) states located above 2 MeV excitation energy in \(^{98}\)Zr. Based on these measurements, ratios of \(B\)(E2) values for transitions to lower-lying levels are determined, highlighting the preferential decay paths of these \(2^+\) states. AbstractPublished by the Jagiellonian University2025authors 

Properties of low-lying states in \(^{100}\)Zr were studied using the GRIFFIN spectrometer at TRIUMF following the \(\beta \) decay of \(^{100}\mathrm {Y}\). Using \(\gamma \)–\(\gamma \) angular correlations, level spins were confirmed and E2/M1 mixing ratios determined with improved precision. Applicability of a two-state mixing model to the observed structures in \(^{100}\mathrm {Zr}\) is explored. AbstractPublished by the Jagiellonian University2026authors 

The nuclear structure of the⁹⁸Zr nucleus was studied through theβ⁻decay of⁹⁸Y_g.s.at the TRIUMF-ISAC facility. The use of the 8π γ-ray spectrometer with its ancillary detectors SCEPTAR and PACES enabled γ-γ and γ-e⁻coincidence measurements as well as γ-γ angular correlations. The level spin assignments and transition mixing ratios obtained in this study were in good agreement with previous results. Furthermore, 12 previously unknown states in the low-energy region of⁹⁸Zr were identified, including the 0⁺₅and 0⁺₆levels at 2418 and 2749 keV, respectively. The 2⁺and I=1 natures for multiple newly observed and previously known (but not firmly assigned) states have been established. Additionally, the previously assumed pureE2 character of the 2⁺₂→ 2⁺₁367.8-keV transition was confirmed. 

This manuscript reports on the direct observation of a $\beta$ -delayed two-neutron emission in a study of ${}^{134}\mathrm{In}$ at the ISOLDE Decay Station using neutron spectroscopy. We also report on the first measurement in ${\beta }^{-}$ decay of the long-sought $13/2^{+}$ excited state in ${}^{133}\mathrm{Sn}$ , attributed to be the neutron single-particle $i_{13/2}$ orbital. The observation of sequential neutron emission is used to extract the relative population of the $i_{13/2}$ state, which was found to be much smaller than the predictions of the statistical model. The experiment was possible because of the innovative use of a neutron array with neutron discrimination and interaction tracking capabilities. This is the first study of the details of the two-neutron emission for a nucleus, which belongs to the $r$ -process path. Understanding $\beta$ -delayed two-neutron emission probabilities is essential to validate models used in astrophysical $r$ -process nucleosynthesis calculations. Observing two-neutron emissions in ${\beta }^{-}$ decay paves the way for new experiments to study energy and angular correlations for $\beta$ -delayed multineutron emitters. 

A campaign of Coulomb-excitation experiments to study the electromagnetic structure of \(^{110}\)Cd was performed using beams of \(^{14}\)N, \(^{32}\)S, and \(^{60}\)Ni. The use of various reaction partners enables disentangling the contributions of individual electromagnetic matrix elements involved in the excitation process, yielding, among others, a precise determination of the lifetime of the 2\(^+_2\) state in \(^{110}\)Cd. AbstractPublished by the Jagiellonian University2025authors