$B(E2;2^{+}_{1}\rightarrow0^{+}_{1})$ anomaly in $^{166}$Os

Chen-guang Zhang; Suo-chang Jin; Tie Wang; Tao Wang

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arXiv · 2509.07692

$B(E2;2^{+}_{1}\rightarrow0^{+}_{1})$ anomaly in $^{166}$Os

Chen-guang Zhang·Suo-chang Jin·Tie Wang·Tao Wang

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Abstract

Recently, the very small $B(E2;2_{1}^{+}\rightarrow0_{1}^{+})$ value was found in $^{166}$Os, which is 7(4) W.u. \textbf{and} much smaller than the values of adjacent nuclei $^{168,170}$Os, 74(13) W.u. and 97(9) W.u.. With the help of a new technique ``SU(3) analysis" and a new explanatory framework of the B(E2) anomaly, it was found that, the $B(E2;2_{1}^{+}\rightarrow0_{1}^{+})$ anomaly really can exist. In this paper, we discuss the $B(E2;2_{1}^{+}\rightarrow0_{1}^{+})$ anomaly in $^{166}$Os for the first time. Four results are used to fit the experimental data in $^{166,168,170}$Os successfully. This implies that the level-crossing or level-anticrossing explanation is more reasonable.

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Chen-guang Zhang, Suo-chang Jin, Tie Wang, Tao Wang. 2025-09-09. $B(E2;2^{+}_{1}\rightarrow0^{+}_{1})$ anomaly in $^{166}$Os. https://arxiv.org/abs/2509.07692

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