重离子碰撞中的张量力效应

doi:10.7523/j.issn.2095-6134.2018.04.005

中国科学院大学学报 ›› 2018, Vol. 35 ›› Issue (4): 457-462.DOI: 10.7523/j.issn.2095-6134.2018.04.005

重离子碰撞中的张量力效应

余冲, 郭璐

中国科学院大学物理科学学院, 北京 100049

收稿日期:2017-04-12 修回日期:2017-05-05 发布日期:2018-07-15
通讯作者: 郭璐
基金资助:
国家自然科学基金面上项目（11175252，11575189）、NSFC-JSPS国际合作项目（11711540016）和中国科学院大学校所合作基金资助

Role of the Skyrme tensor force in heavy-ion collision

YU Chong, GUO Lu

School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China

Received:2017-04-12 Revised:2017-05-05 Published:2018-07-15

摘要/Abstract

摘要： 采用时间相关的Hartree-Fock（TDHF）理论，研究¹⁶O+⁴⁰Ca反应体系中Skyrme张量力对重离子碰撞的影响。数值计算包含Skyrme能量密度泛函中的所有项，在没有任何对称性约束的三维笛卡尔坐标系下完成。TDHF理论微观自洽地包含泡利原理和自旋-轨道作用等量子效应。系统研究张量力对库仑位垒、高能熔合阈值以及Skyrme能量密度泛函中各项能量贡献的影响。发现张量力对自旋饱和体系¹⁶O+⁴⁰Ca的库仑位垒没有影响，但对高能熔合阈值影响较大，同位旋标量和同位旋矢量张量项以及平均场的重排使高能熔合阈值升高。张量力会使Skyrme能量密度泛函中一些项的能量贡献大小发生变化，同位旋标量张量项以及平均场的重排使自旋流赝张量项的总能量贡献增大，同位旋矢量张量项以及平均场的重排使自旋流赝张量项的总能量贡献减小。

Abstract: In this paper, we studied the role of Skyrme tensor force in ¹⁶O +⁴⁰Ca collision using the time-dependent Hartree-Fock (TDHF) theory with the full terms of Skyrme effective interaction. The calculations were carried out in three-dimensional Cartesian bases without any symmetry restrictions. The TDHF theory incorporates various quantum effects including Pauli effect and spin-orbit coupling. We systematically studied effects of the Skyrme tensor force on Coulomb barrier, upper fusion threshold energy, and Skyrme energy density functional for the¹⁶O +⁴⁰Ca system. The Skyrme tensor force has no influence on Coulomb barrier in the spin-saturated system ¹⁶O +⁴⁰Ca, and the tensor force plays a non-negligible role for upper fusion threshold energy. The isoscalar and isovector tensor terms and the rearrangement of mean-field tend to increase the upper fusion threshold energy. The tensor force leads to some changes in Skyrme energy density functional. The isoscalar tensor term and the rearrangement of mean-field increase the total energy contributions of pseudotensor spin-current term, while the isovector tensor term and the rearrangement of mean-field decrease the total energy contributions of pseudotensor spin-current term.

Key words: time-dependent Hartree-Fock, tensor force, Coulomb barrier, upper fusion threshold energy

中图分类号:

O571.6

余冲, 郭璐. 重离子碰撞中的张量力效应[J]. 中国科学院大学学报, 2018, 35(4): 457-462.

YU Chong, GUO Lu. Role of the Skyrme tensor force in heavy-ion collision[J]. , 2018, 35(4): 457-462.

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重离子碰撞中的张量力效应

Role of the Skyrme tensor force in heavy-ion collision

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