论文标题
$^{31} $ f的两中性光环结构和一种新颖的配对抗Halo效应
Two-neutron halo structure of $^{31}$F and a novel pairing anti-halo effect
论文作者
论文摘要
背景：一个新确定的滴灌核$^{31} $ f提供了一个独特的机会，可以在反转岛的东海岸研究两中性（$ 2N $）的相关性，其中$ n = 28 $ shell Cloes丢失了。 目的：我们的目标是介绍$^{31} $ f的半径和总反应横截面的第一个三体理论结果。这将进一步帮助调查$ n = 28 $壳的配对和分解如何影响$ 2N $ -HALO结构的形成和该质量区域的反Halo效应。 方法：$^{29} $ f $+n+n $三体系统由簇轨道壳模型描述，其总反应横截面由Glauber理论计算。 结果：我们的三体计算预测$^{31} $ f的根平方半径为3.48-3.70 FM，这对应于1530（1410）-1640（1500）MB的总反应截面，对于240（900）MEV/unineleon。讨论了$^{31} $ f中的绑定机制和光环形成。 结论：本研究表明，在这个群众区域中有一种新颖的抗哈洛效应：当配对克服$ p_ {3/2} $和$ f_ {7/2} $ orbits之间的能量差距时，这些轨道的占用数量的反转发生，并减少了2n $ -HALO的结构。
Background: A newly identified dripline nucleus $^{31}$F offers a unique opportunity to study the two-neutron ($2n$) correlation at the east shore of the island of inversion where the $N = 28$ shell closure is lost. Purpose: We aim to present the first three-body theoretical results for the radius and total reaction cross sections of $^{31}$F. This will further help to investigate how the pairing and breakdown of the $N = 28$ shell closure influence the formation of the $2n$-halo structure and the anti-halo effect in this mass region. Methods: A $^{29}$F$+n+n$ three-body system is described by the cluster orbital shell model, and its total reaction cross section is calculated by the Glauber theory. Results: Our three-body calculations predict 3.48-3.70 fm for the root-mean-square radius of $^{31}$F, which corresponds to the total reaction cross section of 1530 (1410)-1640 (1500) mb for a carbon target at 240 (900) MeV/nucleon. The binding mechanism and halo formation in $^{31}$F are discussed. Conclusions: The present study suggests a novel anti-halo effect in this mass region: When the pairing overcome the energy gap between the $p_{3/2}$ and $f_{7/2}$ orbits, the inversion of the occupation number of these orbits takes place, and it diminishes the $2n$-halo structure.
