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arXiv · 2306.04517

Binding energies of ground and isomeric states in neutron-rich ruthenium isotopes: measurements at JYFLTRAP and comparison to theory

Abstract

We report on precision mass measurements of $^{113,115,117}$Ru performed with the JYFLTRAP double Penning trap mass spectrometer at the Accelerator Laboratory of University of Jyväskylä. The phase-imaging ion-cyclotron-resonance technique was used to resolve the ground and isomeric states in $^{113,115}$Ru and enabled for the first time a measurement of the isomer excitation energies, $E_x(^{113}$Ru$^{m})=100.5(8)$ keV and $E_x(^{115}$Ru$^{m})=129(5)$ keV. The ground state of $^{117}$Ru was measured using the time-of-flight ion-cyclotron-resonance technique. The new mass-excess value for $^{117}$Ru is around 36 keV lower and 7 times more precise than the previous literature value. With the more precise ground-state mass values, the evolution of the two-neutron separation energies is further constrained and a similar trend as predicted by the BSkG1 model is obtained up to the neutron number $N=71$.

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M. Hukkanen, W. Ryssens, P. Ascher, M. Bender, T. Eronen, S. Grévy, A. Kankainen, M. Stryjczyk, L. Al Ayoubi, S. Ayet, O. Beliuskina, C. Delafosse, Z. Ge, M. Gerbaux, W. Gins, A. Husson, A. Jaries, S. Kujanpää, M. Mougeot, D. A. Nesterenko, S. Nikas, H. Penttilä, I. Pohjalainen, A. Raggio, M. Reponen, S. Rinta-Antila, A. de Roubin, J. Ruotsalainen, V. Virtanen, A. P. Weaver. 2023-10-09. Binding energies of ground and isomeric states in neutron-rich ruthenium isotopes: measurements at JYFLTRAP and comparison to theory. https://doi.org/10.1103/physrevc.108.064315

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