Exploring the Onset of Collectivity Approaching N=40 through Manganese Masses

C. Chambers; M. P. Reiter; A. T. Gallant; M. Yavor; C. Andreoiu; C. Babcock; J. Bergmann; T. Dickel; J. Dilling; E. Dunling; G. Gwinner; Z. Hockenbery; J. D. Holt; R. Klawitter; B. Kootte; Y. Lan; J. Lassen; E. Leistenschneider; R. Li; T. Miyagi; M. Mostamand; W. R. Plaß; C. Scheidenberger; R. Thompson; M. Vansteenkiste; M. E. Wieser; A. A. Kwiatkowski

arXiv · 2502.18610

Exploring the Onset of Collectivity Approaching N=40 through Manganese Masses

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Abstract

Isotopes in the region of the nuclear chart below $^{68}\mathrm{Ni}$ have been the subject of intense experimental and theoretical effort due to the potential onset of a new ``island of inversion'' when crossing the harmonic oscillator subshell closure at $N = 40$. We have measured the masses of $^{64-68}\textrm{Mn}$ using TITAN's multiple-reflection time-of-flight mass spectrometer, resulting in the first precision mass measurements of $^{67}\mathrm{Mn}$ and $^{68}\mathrm{Mn}$. These results are compared to \textit{ab initio} calculations and modern shell model calculations and show an increase in collectivity approaching $N=40$.

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C. Chambers, M. P. Reiter, A. T. Gallant, M. Yavor, C. Andreoiu, C. Babcock, J. Bergmann, T. Dickel, J. Dilling, E. Dunling, G. Gwinner, Z. Hockenbery, J. D. Holt, R. Klawitter, B. Kootte, Y. Lan, J. Lassen, E. Leistenschneider, R. Li, T. Miyagi, M. Mostamand, W. R. Plaß, C. Scheidenberger, R. Thompson, M. Vansteenkiste, M. E. Wieser, A. A. Kwiatkowski. 2025-02-25. Exploring the Onset of Collectivity Approaching N=40 through Manganese Masses. https://arxiv.org/abs/2502.18610

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