학술논문
New $\alpha$-Emitting Isotope $^{214}$U and Abnormal Enhancement of $\alpha$-Particle Clustering in Lightest Uranium Isotopes
Document Type
Working Paper
Author
Zhang, Z. Y.; Yang, H. B.; Huang, M. H.; Gan, Z. G.; Yuan, C. X.; Qi, C.; Andreyev, A. N.; Liu, M. L.; Ma, L.; Zhang, M. M.; Tian, Y. L.; Wang, Y. S.; Wang, J. G.; Yang, C. L.; Li, G. S.; Qiang, Y. H.; Yang, W. Q.; Chen, R. F.; Zhang, H. B.; Lu, Z. W.; Xu, X. X.; Duan, L. M.; Yang, H. R.; Huang, W. X.; Liu, Z.; Zhou, X. H.; Zhang, Y. H.; Xu, H. S.; Wang, N.; Zhou, H. B.; Wen, X. J.; Huang, S.; Hua, W.; Zhu, L.; Wang, X.; Mao, Y. C.; He, X. T.; Wang, S. Y.; Xu, W. Z.; Li, H. W.; Ren, Z. Z.; Zhou, S. G.
Source
Phys. Rev. Lett. 126, 152502 (2021)
Subject
Language
Abstract
A new $\alpha$-emitting isotope $^{214}$U, produced by fusion-evaporation reaction $^{182}$W($^{36}$Ar, 4n)$^{214}$U, was identified by employing the gas-filled recoil separator SHANS and recoil-$\alpha$ correlation technique. More precise $\alpha$-decay properties of even-even nuclei $^{216,218}$U were also measured in reactions of $^{40}$Ar, $^{40}$Ca with $^{180, 182, 184}$W targets. By combining the experimental data, improved $\alpha$-decay reduced widths $\delta^2$ for the even-even Po--Pu nuclei in the vicinity of magic neutron number $N=126$ were deduced. Their systematic trends are discussed in terms of $N_{p}N_{n}$ scheme in order to study the influence of proton-neutron interaction on $\alpha$ decay in this region of nuclei. It is strikingly found that the reduced widths of $^{214,216}$U are significantly enhanced by a factor of two as compared with the $N_{p}N_{n}$ systematics for the $84 \leq Z \leq 90$ and $N<126$ even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the $\pi 1f_{7/2}$ and $\nu 1f_{5/2}$ spin-orbit partner orbits, which is supported by a large-scale shell model calculation.