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arXiv 0908.2678nucl-thnucl-ex
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相对论平均场论中具有$ω$介子矢量自耦合的超重核

Superheavy nuclei with the vector self-coupling of the $ω$-meson in the relativistic mean-field theory

A A Saldanha, A R Farhan, M M Sharma

摘要:

本文在RMF理论框架下研究了Z=102 ~ Z=120超重元素的性质和壳层结构。研究范围涵盖中子数N=150-190的核素。本文采用了考虑ω介子矢量自耦合的拉格朗日模型NL-SV_1。我们对轴向变形核组态进行了RMF + BCS计算。从平均场最小化出发,得到了基态结合能、单粒子性质和核的四极形变。对双中子分离能、$Q_α$值和α衰变半衰期进行了评价。结果表明,在超重元素的一个重要区域内,大量核素表现出形状共存现象。在远低于N=184的核素中,长方形和扁方形的形状共存是普遍的,而在N=184附近的核倾向于显示球形和扁方形之间的形状共存。壳层结构和2-中子分离能得到的RMF理论加强了中子数N=184作为一个主要的幻数。结果表明,在变形区,中子数N=172的行为类似于幻数。结果表明,Z=120和N=172的组合在超重区具有成为双幻数的潜力。

英文摘要:

We have studied properties and shell structure of the superheavy elements from Z=102 to Z=120 within the framework of the RMF theory. The region of study spans nuclides with neutron numbers N=150-190. The Lagrangian model NL-SV1 with the inclusion of the vector self-coupling of the omega-meson has been employed in this work. We have performed RMF + BCS calculations for an axially deformed configuration of nuclei. The ground-state binding energies, single-particle properties and quadrupole deformation of nuclei have been obtained from the mean-field minimizations. Two-neutron separation energies, $Q_α$ values and alpha-decay half-life have been evaluated. It is shown that a large number of nuclides exhibit the phenomenon of shape-coexistence over a significant region of the superheavy elements. Shape coexistence of a prolate and an oblate shape is prevalent in nuclides far below N=184, whilst nuclei in the vicinity of N=184 tend to show a shape coexistence between a spherical and an oblate shape. The shell structure and 2-neutron separation energies obtained with the RMF theory reinforce the neutron number N=184 as a major magic number. It is shown that the neutron number N=172 acts akin to a magic number in the deformed region. It is suggested that the combination Z=120 and N=172 has the potential of being a doubly magic number in the superheavy region.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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