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

• Main Authors: Chambers, C, Reiter, M. P, Gallant, A. T, Yavor, M, Andreoiu, C, Babcock, C, Bergmann, J, Dickel, T, Dilling, J, Dunling, E, Gwinner, G, Hockenbery, Z, Holt, J. D, Klawitter, R, Kootte, B, Lan, Y, Lassen, J, Leistenschneider, E, Li, R, Miyagi, T, Mostamand, M, Plaß, W. R, Scheidenberger, C, Thompson, R, Vansteenkiste, M, Wieser, M. E, Kwiatkowski, A. A
• Format: Journal Article
• Language: English
• Published: 25.02.2025
• Subjects: Physics - Nuclear Experiment
• DOI: 10.48550/arxiv.2502.18610

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 $N=40$.