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arXiv · 1204.5527

Understanding the different rotational behaviors of $^{252}$No and $^{254}$No

H. L. Liu·F. R. Xu·P. M. Walker
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Abstract

Total Routhian surface calculations have been performed to investigate rapidly rotating transfermium nuclei, the heaviest nuclei accessible by detailed spectroscopy experiments. The observed fast alignment in $^{252}$No and slow alignment in $^{254}$No are well reproduced by the calculations incorporating high-order deformations. The different rotational behaviors of $^{252}$No and $^{254}$No can be understood for the first time in terms of $β_6$ deformation that decreases the energies of the $νj_{15/2}$ intruder orbitals below the N=152 gap. Our investigations reveal the importance of high-order deformation in describing not only the multi-quasiparticle states but also the rotational spectra, both providing probes of the single-particle structure concerning the expected doubly-magic superheavy nuclei.

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H. L. Liu, F. R. Xu, P. M. Walker. 2012-06-20. Understanding the different rotational behaviors of $^{252}$No and $^{254}$No. https://doi.org/10.1103/physrevc.86.011301

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