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Abstract Model-observation comparisons of type-I X-ray bursts (XRBs) can reveal the properties of accreting neutron star systems, including the neutron star compactness. XRBs are powered by nuclear burning, and a handful of reactions have been shown to impact the model results. Reactions in the NiCu cycles, featuring a competition between⁵⁹Cu(p,γ)⁶⁰Zn and⁵⁹Cu(p,α)⁵⁶Ni, have been shown to be among the most important reactions as they are a critical checkpoint inrp-process flow and significantly impact the light curves and burst ashes. We report a direct measurement of⁵⁹Cu(p,α)⁵⁶Ni, bringing stringent constraints on this reaction rate. New results rule out a strong NiCu cycle in XRBs, with a negligible degree of recycling, ≤5% up to 1.5 GK. The new reaction rate, when varied within new uncertainty limits, shows no impact on one-zone XRB model light curves tailored for clocked-bursterGS1826–24, hence removing an important nuclear physics uncertainty in the model-observation comparison. 

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 

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 

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