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arXiv · 2502.18076

Microscopic investigation of $E2$ matrix elements in atomic nuclei

S. P. Rouoof·Nazira Nazir·S. Jehangir·G. H. Bhat·J. A. Sheikh·N. Rather·S. Frauendorf
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Abstract

A systematic analysis of $E2$ matrix elements of $^{72}$Ge, $^{76}$Ge, $^{168}$Er, $^{186}$Os, $^{188}$Os, $^{190}$Os, $^{192}$Os and $^{194}$Pt nuclides is performed using the beyond mean-field approach of triaxial projected shell model (TPSM). For these nuclei, large sets of $E2$ matrix elements have been deduced from the multi-step Coulomb excitation experiments, and it is shown that TPSM approach provides a reasonable description of the measured transitions. We have evaluated 1496 $E2$ matrix elements up to spin, $I=10$ for the eight nuclei studied, and tabulate them for future experimental and theoretical comparisons. Further, shape invariant analysis has been performed with the calculated $E2$ transitions using the Kumar-Cline sum rules. It is inferred from the analysis that the resulting shape, after configuration mixing of the quasiparticle states, transforms from $\gamma$-rigid to that of $\gamma$-soft for some nuclei, in conformity with the experimental data.

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S. P. Rouoof, Nazira Nazir, S. Jehangir, G. H. Bhat, J. A. Sheikh, N. Rather, S. Frauendorf. 2025-02-25. Microscopic investigation of $E2$ matrix elements in atomic nuclei. https://arxiv.org/abs/2502.18076

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