Search for: All records

Nuclear shape coexistence is a widespread but not yet well understood phenomenon. Electric monopole (E0) transitions are a particularly sensitive probe of shape coexistence. The firstE0measurements on the Cr isotopes were performed at The Australian National University, but were hampered by missing and imprecise data of the key spectroscopic quantities such as level lifetimes. To address these needs, the low-lying states in⁵²Cr were investigated at the University of Kentucky Accelerator Laboratory with inelastic neutron scattering. γ-ray angular distribution and excitation function measurements were performed to determine level lifetimes, spins and parities, transition mixing ratios, and γ-ray branching ratios. We present new level lifetimes for three states in⁵²Cr along with the implications for E0 transition strengths and shape coexistence in⁵²Cr. 

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. 

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