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arXiv · 1305.2965

Spins and Magnetic Moments of $^{49}$K and $^{51}$K: establishing the 1/2$^+$ and 3/2$^+$ level ordering beyond $N$ = 28

J. Papuga·M. L. Bissell·K. Kreim·K. Blaum·B. A. Brown·M. De Rydt·R. F. Garcia Ruiz·H. Heylen·M. Kowalska·R. Neugart·G. Neyens·W. Nörtershäuser·T. Otsuka·M. M. Rajabali·R. Sánchez·Y. Utsuno·D. T. Yordanov
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Abstract

The ground-state spins and magnetic moments of $^{49,51}$K have been measured using bunched-beam high-resolution collinear laser spectroscopy at ISOLDE-CERN. For $^{49}$K a ground-state spin $I = 1/2$ was firmly established. The observed hyperfine structure of $^{51}$K requires a spin $I > 1/2$ and from its magnetic moment $\mu(^{51}\text{K})= +0.5129(22)\, \mu_N$ a spin/parity $I^\pi=3/2^+$ with a dominant $\pi 1d_{3/2}^{-1}$ hole configuration was deduced. This establishes for the first time the re-inversion of the single-particle levels and illustrates the prominent role of the residual monopole interaction for single-particle levels and shell evolution.

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J. Papuga, M. L. Bissell, K. Kreim, K. Blaum, B. A. Brown, M. De Rydt, R. F. Garcia Ruiz, H. Heylen, M. Kowalska, R. Neugart, G. Neyens, W. Nörtershäuser, T. Otsuka, M. M. Rajabali, R. Sánchez, Y. Utsuno, D. T. Yordanov. 2013-05-13. Spins and Magnetic Moments of $^{49}$K and $^{51}$K: establishing the 1/2$^+$ and 3/2$^+$ level ordering beyond $N$ = 28. https://doi.org/10.1103/physrevlett.110.172503

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