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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 

Abstract Lifetimes of excited states in$$^{162}$$ $_{}^{162}$ Dy were measured using the (n,n’$$\gamma $$ $\gamma$ ) reaction with the Doppler-Shift Attenuation Method (DSAM) at the University of Kentucky’s Accelerator Laboratory. A total of eighteen level lifetimes were obtained, including eleven negative-parity states, seven of which are new. These measurements significantly expand the experimental database of transition probabilities for negative-parity bands in the well-deformed rare earth region of nuclei. The extracted B(E1) and B(E2) values reveal enhanced interband E1 ($$10^{-3}$$ ${10}^{-3}$ or$$10^{-4}$$ ${10}^{-4}$ ) W.u. and E2 strengths (several W.u.) between negative- and positive parity bands, particularly for the KEquation missing<#comment/>bands decaying to the the K$$^{\pi }=2^+_{\gamma }$$ $_{}^{\pi }=2_{\gamma }^{+}$ band, consistent with signatures of octupole-quadrupole coupling. In contrast, the K$$^{\pi }=0^-_1$$ $_{}^{\pi }=0_1^{-}$ and K$$^{\pi }=1^-_3$$ $_{}^{\pi }=1_3^{-}$ bands, which exhibit strong E1 transitions to the ground state band, are indicative of octupole-vibrational excitations built on the deformed ground state. Comparison of transition rates with Alaga rules supports this interpretation and distinguishes collective excitations from likely quasi-particle states. These new results establish$$^{162}$$ $_{}^{162}$ Dy as the most extensively characterized rare-earth nucleus for negative parity lifetimes and provide critical experimental benchmarks for theoretical models. 

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 

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 

Abstract The electricE1 and magneticM1 dipole responses of the$$N=Z$$ $N=Z$ nucleus$$^{24}$$ ${}^{24}$ Mg were investigated in an inelastic photon scattering experiment. The 13.0 MeV electrons, which were used to produce the unpolarised bremsstrahlung in the entrance channel of the$$^{24}$$ ${}^{24}$ Mg($$\gamma ,\gamma ^{\prime }$$ $\gamma ,{\gamma }^{\prime }$ ) reaction, were delivered by the ELBE accelerator of the Helmholtz-Zentrum Dresden-Rossendorf. The collimated bremsstrahlung photons excited one$$J^{\pi }=1^-$$ $J^{\pi }=1^{-}$ , four$$J^{\pi }=1^+$$ $J^{\pi }=1^{+}$ , and six$$J^{\pi }=2^+$$ $J^{\pi }=2^{+}$ states in$$^{24}$$ ${}^{24}$ Mg. De-excitation$$\gamma $$ $\gamma$ rays were detected using the four high-purity germanium detectors of the$$\gamma $$ $\gamma$ ELBE setup, which is dedicated to nuclear resonance fluorescence experiments. In the energy region up to 13.0 MeV a total$$B(M1)\uparrow = 2.7(3)~\mu _N^2$$ $B\left(M1\right)\uparrow =2.7\left(3\right){\mu }_N^2$ is observed, but this$$N=Z$$ $N=Z$ nucleus exhibits only marginalE1 strength of less than$$\sum B(E1)\uparrow \le 0.61 \times 10^{-3}$$ $\sum B\left(E1\right)\uparrow \le 0.61\times {10}^{-3}$  e$$^2 \, $$ ${}^2$ fm$$^2$$ ${}^2$ . The$$B(\varPi 1, 1^{\pi }_i \rightarrow 2^+_1)/B(\varPi 1, 1^{\pi }_i \rightarrow 0^+_{gs})$$ $B(\Pi 1,1_i^{\pi }\to 2_1^{+})/B(\Pi 1,1_i^{\pi }\to 0_{\mathrm{gs}}^{+})$ branching ratios in combination with the expected results from the Alaga rules demonstrate thatKis a good approximative quantum number for$$^{24}$$ ${}^{24}$ Mg. The use of the known$$\rho ^2(E0, 0^+_2 \rightarrow 0^+_{gs})$$ ${\rho }^2(E0,0_2^{+}\to 0_{\mathrm{gs}}^{+})$ strength and the measured$$B(M1, 1^+ \rightarrow 0^+_2)/B(M1, 1^+ \rightarrow 0^+_{gs})$$ $B(M1,1^{+}\to 0_2^{+})/B(M1,1^{+}\to 0_{\mathrm{gs}}^{+})$ branching ratio of the 10.712 MeV$$1^+$$ $1^{+}$ level allows, in a two-state mixing model, an extraction of the difference$$\varDelta \beta _2^2$$ $\Delta {\beta }_2^2$ between the prolate ground-state structure and shape-coexisting superdeformed structure built upon the 6432-keV$$0^+_2$$ $0_2^{+}$ level. 

Neutron elastic scattering cross sections on natural carbon serve as a reference standard in the incident energy range 10 eV to 1.8 MeV. The 2017 standards evaluation [1, 2] is 0.5 to 2.0% higher in that energy range than the 2006 standards evaluation [3]. In addition the ENDF/B-VIII.0 release split the natural carbon cross sections into the isotopes¹²C,¹³C, and¹⁴C for the first time. These details call for the re-measurement of the¹³C cross sections in sensitive regions. Ten elastic scattering angular distributions were recently measured for incident neutron energies between 0.5 and 3.25 MeV at the University of Kentucky Accelerator Laboratory (www.pa.uky.edu/accelerator/) using nanosecond pulsed beams and time-of-flight techniques. An overview of neutron production and detection, the new digital data acquisition system, and data analysis will be presented. Results are compared with data from previous measurements and database evaluations. 

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. 

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.