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The low-lying structure of⁷⁴Ge has been studied with γ-ray detection following inelastic neutron scattering. From excitation function and angular distribution data, the levels and transitions have been characterized including level spins and lifetimes, branching ratios, and multipole mixing ratios. In addition, a number of levels found in the literature for⁷⁴Ge appear to be erroneously placed. Upon removal of these states from the level scheme, excellent agreement with large-scale shell-model calculations was obtained. 

γ-ray production cross sections have been deduced for reactions with incident neutrons having energies from 1.5 - 4.7 MeV. Similar measurements were made on a natural Ti sample to establish an absolute normalization. The resulting γ-ray production cross sections are compared to TENDL and TALYS calculations, as well as data from previous measurements. The models are found to describe the production cross sections for mostγrays observed from⁵⁴Mn and⁵⁴Fe rather well. 

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 

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. 

Lead-208 is the heaviest known doubly magic nucleus and its structure is therefore of special interest. Despite this magicity, which acts to provide a strong restorative force toward sphericity, it is known to exhibit both strong octupole correlations and some of the strongest quadrupole collectivity observed in doubly magic systems. In this Letter, we employ state-of-the-art experimental equipment to conclusively demonstrate, through four Coulomb-excitation measurements, the presence of a large, negative, spectroscopic quadrupole moment for both the vibrational octupole $3_1^{-}$and quadrupole $2_1^{+}$state, indicative of a preference for prolate deformation of the states. The observed quadrupole moment is discussed in the context of the expected splitting of the $3^{-}\otimes 3^{-}$two-phonon states, due to the coupling of the quadrupole and octupole motion. These results are compared with theoretical values from three different methods, which are unable to reproduce both the sign and magnitude of this deformation. Thus, in spite of its well-studied nature, ${}^{208}\mathrm{Pb}$remains a puzzle for our understanding of nuclear structure. Published by the American Physical Society2025